Aris Messinis / AFP - Getty Images

A woman walks past graffiti in the center of Athens on October 23.

LONDON -- The world's markets may believe that the worst of the financial crisis in Europe is over after three turbulent years, but those people who control the purse strings of the world's businesses are not breathing any easier.

An annual survey of finance directors from global business consultancy BDO finds that the crisis over too much government debt in Europe remains one of their key concerns — so much so that Greece is considered a riskier place to invest and set up business in than war-torn Syria.

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Only Iran and Iraq are considered more risky than Greece, which also struggles to convince its international creditors that it deserves bailout loans to avoid bankruptcy and a possible euro exit.

"CFOs are becoming increasingly wary of Southern Europe, parts of which they now see as risky as the politically unstable countries of the Middle East," said BDO chief executive Martin Van Roekel.

Greece isn't the only country in the 17-country group that uses the euro in the survey's top 10 riskiest countries to invest in. Spain, which even as the eurozone's No. 4 economy with a long-standing relationship with Latin America, stands at No. 7.

Hate crimes increase, extreme right strengthens as Greece economy sinks

This reluctance by finance directors, particularly from fast-growing economies such as Brazil and China, to invest in Europe's indebted countries goes to the heart of the financial crisis. A major part of these countries' recovery is dependent on the private sector stepping in to fill the investment gap left by cuts in government spending.

While countries like Greece and Spain are struggling to convince international business that they are good places to invest, others are prospering. Despite recent signs of slowing down, China is considered the most attractive country for expansion, closely followed by the U.S. Others such as Brazil, India, Germany and the U.K. also feature in the top 10 of countries ripe for expansion.

PhotoBlog: 'Enough is enough': Striking Greeks clash with police

Overall, the survey from BDO found that CFOs around the world are finding it more difficult to conduct business abroad. As well as an uncertain global economic situation, they cite increased regulation and greater competition.

Van Roekel also said he is "surprised" that more finance directors haven't voiced concerns about the heavy debts of countries outside of Europe, notably Japan and the U.S.

Though Japan's debt is worth around double the size of its economy, the country has managed to avoid stoking too many investor concerns because most of its self-financed by its own pension funds.

The U.S., which has the advantage of having the dollar, the world's reserve currency, has problems of its own and the winner of the presidential election, whoever it is, will soon have to grapple with the "fiscal cliff" — a package of huge tax hikes and spending cuts that will automatically be introduced if the different arms of government don't come to a budget agreement.

BDO surveyed 1,000 CFOs from medium-sized companies currently planning foreign investment.

Read more coverage of Greece on nbcnews.com

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"When police arrived they called an ambulance, but then told me that they could not help me any further and left," Rahimi recalled, explaining how he only realized how serious his injuries were after spotting blood running out from under his T-shirt during the brutal attack on Sept. 17, 2011.

Rahimi's case does not appear to be unique. As the euro zone debt crisis leaves Greece grappling with a 25 percent overall unemployment rate, activists say they have noted an increase in the number of hate crimes reported.

'It is virtually impossible to find a job': Brain drain is new Greek tragedy

Far-right populism has also found fertile ground in the near-bankrupt country, where the economy is forecast to contract by 7 percent this year and every second youth is out of work.

Nazi-style salutes
The Golden Dawn party – no more than an extremist fringe group when it was established in the late 1980s and which has been branded "neo-Nazi" by its opponents – has been gaining support amid the country's deteriorating economic situation.

Citing a poll by VPRC which appeared in the "Ellada Avrio" newspaper on Friday, Reuters reported:

Backing for the ultra-nationalist Golden Dawn, which has been linked to a rise in attacks against migrants in recent months, stood at 14 percent, double their take in June elections that gave the party a foothold in parliament. That would make the group the country's third largest party.

The party's rabidly anti-immigrant message has stuck a chord with many voters as EU/IMF imposed austerity propels unemployment levels to a record 25 percent.

Golden Dawn denies it is neo-Nazi but bears a Swastika-like emblem and its supporters have been seen giving Nazi-style salutes. The party's leader, Nikolaos Mihaloliakos, has denied the Holocaust occurred while one lawmaker, Eleni Zaroulia, called immigrants "sub-humans" in parliament on Thursday.

Reuters added that the opinion poll showed that "Greeks' frustration with their political leaders has grown as the coalition prepares to push through the new round of austerity measures to appease [foreign] lenders and secure more bailout aid and keep the country afloat."

Alkis Konstantinidis / EPA, file

Migrants are held during a police ID-check operation in Athens, Greece, on August 6.

Over the past decade, Greece has become the major gateway into the European Union for illegal immigrants and asylum-seekers from Asia and Africa.

'Growing despair'
Experts estimate that between 800,000 and 1 million undocumented migrants now live in Greece, a country with a population of nearly 11 million.

"The rapid increase of illegal immigration in the past years, growing despair over the ailing economy and a loss of trust in our political leadership have fueled public anger and given way to dangerous populism in the country," says Loukas Tsoukalis, head of Greek think-tank Eliamep.

Campaigning on a message of ultra-nationalism and fierce anti-immigrant policies, Golden Dawn won 18 seats in parliament during June's national election.

"We have to protect 10 million Greeks that are suffering from the very bad economy and from the killings, rapes, shootings and everything else that all illegal immigrants are doing to this country," Ilias Panagotiaros, a Golden Dawn politician and a member of Greek parliament, told NBC News.

Andy Eckardt / NBC News

Ilias Panagiotaros of Greece's far-right Golden Dawn Party.

A poll last month found that the popularity of Nikos Mihalolioakos, head of the Golden Dawn party, has climbed to 22 percent, up 8 points from May.

However, it is not just a harsh political message that has been drawing support for Golden Dawn.

In an attempt to build an image of social responsibility, followers of the movement have taken up the roles of what some Greeks call "a crumbling public support system."

'For Greeks only'
Last month, members of Golden Dawn set up booths in a central Athens square to distribute groceries and collect blood donations. "For Greeks only" was the message, after visitors were asked to provide identification of Greek citizenship.

"Golden Dawn has been taking advantage of the growing despair, presents itself as a protector of the weak and vulnerable," analyst Tsoukalis says. "In dangerous neighborhoods they have offered to escort old ladies to the grocery store around the corner."

Rising political and socio-economic discontent, nurtured by a surge of crime rates in major Greek cities, have also led to widespread public acceptance that followers of Golden Dawn sometimes substitute for police and other government officials.

A video shot in early September shows members of Golden Dawn checking work permits at a local market in Rafina, where migrant vendors sell their goods. Minutes later, several people with black Golden Dawn T-shirts and Greek flags moved in and destroyed the stands.

"We are going to defend our country, our history, our religion, our culture," Golden Dawn's Panagiotaros adds. He is also one of the founders of a ultra-nationalistic football fan club called Galazia Stratia, or Blue Army, that has vowed to "defend Greek national pride inside the stadiums".

Spain's economic crisis turns middle-class families into illegal squatters

In September, José Manuel Barroso, the president of the European Commission, included a stark warning in his annual 'state of the union' address, saying that the euro crisis was contributing to the rise in extremism.

And in recent months, officials in Athens have vowed to set up a special police force to combat violence against migrants and plan to impose tougher penalties for these type of crimes.

"Something must happen quick," says Judith Sunderland from Human Rights Watch, who is author of a report called "Hate on the Streets: Xenophobic violence in Greece."  

“Xenophobic hate crimes have reached an alarming proportion in Greece," she added. "Victims are often actively discouraged from filing complaints, told by police officers that it is not worth their while or that they should fight back themselves. And many migrants fear that they could be locked up themselves because of their legal status."

'The country is on its knees': Ireland grapples with economic collapse

Meanwhile, Rahimi is still waiting for justice in the wake of his attack. The trial has been postponed seven times already in the past year.

"And it remains unclear, whether the prosecutor will argue that the attack had been motivated by racist or xenophobic sentiment," Sunderland told NBC News.

In debt or jobless, many Italians choose suicide

One of the three accused is Themis Skordeli, a female member of Golden Dawn, who failed to get elected to parliament last May.

According to local media reports, Skordeli has been identified as a member of a so called 'anti-migrant patrol group', which was formed to 'work the streets' of poorer Athens' neighborhoods.

Rahimi, who came to Greece in 2005, says that he now rarely leaves his apartment and has become extremely cautious when going out to visit friends.

"I am afraid to live here," he says. "I will wait until the trial is over and then definitely head to another country."

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Orestis Panagiotou / EPA

Workers shout slogans in front of the Greek Parliament during a general strike in Athens, Greece on Thursday. Greek trade unions called a 24-hour general strike to oppose new austerity measures.

ATHENS - Greek police clashed with anti-austerity protesters hurling stones and gasoline bombs on the day of a general strike that brought much of the near-bankrupt country to a standstill.

In the second major walkout in three weeks on Thursday, almost 40,000 protesters marched in Athens in a bid to show EU leaders meeting in Brussels that new wage and pension cuts will only worsen their plight after five years of recession.

Tensions mounted when a small group of protesters began throwing pieces of marble, bottles and gas bombs at police barricading part of the square in front of parliament, prompting riot police to fire several rounds of teargas to disperse them.

Thanassis Stavrakis / AP

Protesters throw gas bombs at riot police officers during a 24-hour nationwide general strike in Athens on Thursday.

A 65-year old protester died of a heart attack, hospital sources told Reuters. Greek media, however, were reporting the man was tear-gassed, the BBC’s correspondent in Athens, Mark Lowen reported.

Another three people were injured. Police detained about 50 protesters suspected of attacking them.

Most business and public sector activity ground to a halt at the start of the 24-hour strike called by the country's two biggest labor unions, ADEDY and GSEE.

Thanassis Stavrakis / AP

Protesters clash with riot police in Athens, during a 24-hour nationwide general strike on Thursday. Greece was facing its second general strike in a month Thursday as workers protested over another batch of austerity measures that are designed to prevent the bankruptcy of the country.

PhotoBlog: Striking Greeks clash with police

"Enough is enough. They've dug our graves, shoved us in and we are waiting for the priest to read the last words," said Konstantinos Balomenos, a 58-year-old worker at a water utility whose wage has been halved to 900 euros and who has two unemployed sons.

It was the third time since late September that tens of thousands of Greeks have taken to the streets holding banners and chanting slogans to show their anger at austerity policies imposed by EU and IMF lenders in exchange for aid.

Thousands of Greeks protest Angela Merkel visit

Some were carrying Greek, Spanish and Portuguese flags and shouted: "EU, IMF out".

"Agreeing to catastrophic measures means driving society to despair and the consequences as well as the protests will then be indefinite," said Yannis Panagopoulos, head of the GSEE private sector union, one of two major unions that represent about 2 million people, or half of Greece's workforce.

Greece is stuck in its worst downturn since World War Two and must make at least 11.5 billion euros of cuts to satisfy the "troika" of the European Commission, European Central Bank and IMF, and secure the next tranche of a 130-billion-euro bailout.

Lenders demand austerity
European Union leaders will try to bridge their differences over plans for a banking union at a two-day summit which starts on Thursday. No substantial decisions are expected, reviving concerns about complacency in tackling the debt crisis which exploded three years ago in Greece. 

The austerity policies being pursued in Europe's indebted Mediterranean countries at the behest of Germany and other rich euro zone members will drive the euro apart, protesters warned.

"This can't go on. We sure need measures but not as tough as the ones (German Chancellor Angela) Merkel is asking for," said Dimitris Mavronassos, a 40-year-old shipyard worker who has not been paid for six months.

The strike emptied streets and offices in Athens. Ships stayed in port, Athens public transport was disrupted and hospitals were working with emergency staff, while public offices, ministries, bakeries and other shops were shut.

Newspaper kiosk owners, lawyers, taxi drivers and air traffic controllers were among those protesting over the cuts, which include further drastic reductions in welfare and health spending.

Rising anger
Opinion polls show rising anger with the terms of the bailout keeping the economy afloat, and Greeks becoming increasingly pessimistic about their country's future. 

"The new, painful package should not be passed," the ADEDY public sector union said in a statement.

"The new demands will only finish off what's left of our labor, pension and social rights."

But with Greece due to run out of money next month, Athens has little choice but to push through the austerity package being discussed with lenders.

Greece and inspectors from the troika say they have agreed on most issues. Athens is expected to secure aid needed to avoid bankruptcy given EU determination to avoid fresh market turmoil threatening bigger economies such as Spain and Italy.

But the protests are expected to increase pressure on Greece's fragile three-party coalition cobbled together in June to implement the harsh austerity terms under its international 130-billion euro bailout agreed in March.

Emboldened by the strikes, the main opposition Syriza party turned up the heat on the government.

"Their time is running out," said the party's 38-year old leader Alexis Tsipras who took part in the march.

"People are taking matters into their own hands."

Reuters contributed to this report.

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Thanassis Stavrakis / AP

Protesters throw petrol bombs at riot police officers during a 24-hour nationwide general strike in Athens on Oct. 18, 2012.

Orestis Panagiotou / EPA

Workers shout slogans in front of the Greek Parliament during a general strike in Athens on October 18, 2012. Greek trade unions called a 24-hour general strike to oppose new austerity measures.

Thanassis Stavrakis / AP

Protesters clash with riot police in Athens on Oct. 18, 2012.

Reuters reports — Greek riot police fired teargas to disperse demonstrators protesting outside parliament on Thursday against a new wave of wage and pension cuts demanded by foreign lenders.

Tens of thousands of Greeks took to the streets in Athens on the day of a general strike that brought much of the country to a standstill. Tensions rose when protesters began hurling petrol bombs and stones at police blocking off parts of the main square before parliament.

"Enough is enough. They've dug our graves, shoved us in and we are waiting for the priest to read the last words," said Konstantinos Balomenos, a 58-year-old worker at a water utility whose wage has been halved to 900 euros and has two unemployed sons. Read more about the background to Thursday's strike.

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Dimitri Messinis / AP

Protestors run away from tear gas during clashes in front of the parliament in Athens on Tuesday Oct. 9, 2012.

Dimitri Messinis / AP

Riot police fight with demonstrators during clashes in front of the parliament in Athens on Tuesday Oct. 9, 2012.

Panagiotis Moschandreou / AFP - Getty Images

Greek Prime Minister Antonis Samaras welcomes German Chancellor Angela Merkel on October 9, 2012 at the airport in Athens.

Yannis Behrakis / Reuters

People hold a banner saying "Frau Merkel get out" ahead of a demonstration against the visit of German Chancellor Angela Merkel in central Athens, October 9, 2012.

Yannis Behrakis / Reuters

Demonstrators, dressed as Nazis, wave a swastika flag as they ride in an open-top car in Syntagma Square in Athens as they protest against the visit of Germany's Chancellor Angela Merkel, October 9, 2012.

Sakis Mitrolidis / AFP - Getty Images

A man in chains and carrying a wooden cross marked "Greece wake up" walks during a protest against the visit of German Chancellor Angela Merkel in Thessaloniki on October 9, 2012.

John Kolesidis / Reuters

A naked protester runs past the parliament in Syntagma Square in Athens during a violent protest against the visit of Germany's Chancellor Angela Merkel October 9, 2012.

Germany's Angela Merkel arrived in Greece on her first visit since Europe's debt crisis erupted here three years ago, braving protests to deliver a message of support - but no new money - to a nation hammered by recession and fighting to stay in the euro. Athens went into security lock down for the visit as some 50,000 protesters made a show of discontent against painful austerity cuts. 

Story: Global economic slowdown is getting worse

Story: Snipers, commandos to welcome Merkel in Greece

Updated at 8:30 a.m. ET The International Monetary Fund said the global economic slowdown is worsening as it cut its growth forecasts for the second time since April and warned U.S. and European policymakers that failure to fix their economic ills would prolong the slump. 

Global growth in advanced economies is too weak to bring down unemployment and what little momentum exists is coming primarily from central banks, the IMF said in its World Economic Outlook, released ahead of its twice-yearly meeting, which will be held in Tokyo later this week. 

"A key issue is whether the global economy is just hitting another bout of turbulence in what was always expected to be a slow and bumpy recovery or whether the current slowdown has a more lasting component," it said. "The answer depends on whether European and U.S. policymakers deal proactively with their major short-term economic challenges." 

Hannbial Hanschke / EPA

Greek Prime Minister Antonis Samaras receives German Chancellor Angela Merkel at the airport in Athens on Tuesday.

Meanwhile, German Chancellor Angela Merkel arrived in Greece on her first visit since Europe's debt crisis erupted here three years ago, braving protests to deliver a message of support -- but no new money -- to a country seen by many as a prime example of Europe's ongoing and entrenched economic woes.

Greece ramps up security ahead of Merkel visit

Thousands of Greeks defied a ban on protests, gathering in Syntagma square in central Athens as Merkel's plane touched down. Two protesters dressed in German military uniforms waved a red-black-and-white swastika flag and held out their arms in the Nazi salute.  

PhotoBlog: Merkel greeted warmly by PM, but not by Greeks

Many Greeks blame Merkel, who is holding talks with conservative Prime Minister Antonis Samaras, for forcing painful cuts on Greece in exchange for two EU-IMF bailout packages totaling over 200 billion euros. 

Fiscal cliff
Ahead of the IMF's Tokyo meeting, policymakers have flagged the U.S. "fiscal cliff" -- government spending cuts and tax raises due to take affect early in 2013 -- and resolving the euro area's debt crisis as the top issues facing the global economy. 

Europe's debt crisis is "a clear and present danger," Canadian Finance Minister Jim Flaherty said last week. 

The IMF forecast that global output in 2012 would grow just 3.3 percent, down from a July estimate of 3.5 percent. 

That would make this the slowest year of growth since 2009 when the world was struggling to pull out of the global financial crisis. It predicted only a modest pickup next year to 3.6 percent, below its July estimate of 3.9 percent. 

It projected U.S. growth would be a little more than 2 percent this year and next, but forecast a contraction in the euro area this year by 0.4 percent and modest growth in 2013 of 0.2 percent. 

Emerging markets are still expected to grow four times as fast as advanced economies, but the IMF took a sharp knife to its estimates for India and Brazil, with the latter now seen growing slower than the United States this year. 

Households could face average $3,500 tax hit if Congress can't avoid 'fiscal cliff'

It also cut its expectations for China in 2012 and 2013 but warned against being overly pessimistic about the prospects of these economies, which were major engines of growth in the global financial crisis. 

"Let me be clear. We do not see these developments as signs of a hard landing in any of these countries," IMF Chief Economist Olivier Blanchard said at a briefing, referring to China, India and Brazil. 

More at work
The IMF said "familiar" forces were dragging down growth in advanced economies -- fiscal consolidation and a still-weak financial system, the same problems that have plagued the world since the global financial crisis exploded in 2008. 

"More seems to be at work, however, than these mechanical forces -- namely, a general feeling of uncertainty," Blanchard said in a commentary on the forecasts. 

Measures of risk and uncertainty remain at low levels, Blanchard pointed out, which makes it difficult to assess the nature of the uncertainty. 

"Worries about the ability of European policymakers to control the euro crisis and worries about the failure to date of U.S. policymakers to agree on a fiscal plan surely play an important role, but one that is hard to nail down," Blanchard said. 

The IMF said financial conditions are likely to remain "very fragile" over the near term because repairing euro zone problems will take time and there are concerns about how the U.S. economy will cope with the expected spending cuts and tax increases. 

Boehner 'not confident at all' fiscal cliff can be avoided

The "urgent policy priorities" for the United States should include avoiding the fiscal cliff, which the IMF said at the extreme would amount to a fiscal withdrawal of more than 4 percent of GDP in 2013, and economic growth would stall. 

"Both sides of the political aisle (should) signal that they are willing to compromise and that they're willing to get this done ... that could help lower the level of uncertainty that is affecting U.S. investors and consumers," IMF First Deputy Managing Director David Lipton told Reuters in an interview on Monday. 

Resolving the euro area crisis would require progress in adopting and implementing the various measures discussed, including banking and fiscal union, the IMF report said. 

"If the complex puzzle can be rapidly completed, one can reasonably hope that the worst might be behind us," Blanchard said. 
Euro zone finance ministers on Monday unveiled the European Stability Mechanism (ESM), a 500 billion euro rescue mechanism for lending to distressed economies in the 17-country bloc. 

Merkel Greece visit
Police have readied 6,000 officers, including anti-terrorist units and rooftop snipers, to provide security during Merkel's six-hour visit. German sites in the Greek capital, including the embassy and Goethe Institute, are under special protection. 

Merkel was given the red carpet treatment and full military honors at Athens airport. Samaras greeted her with a handshake as she exited the German air force jet. A band played the German and Greek national anthems. 

In the center of Athens, the reception was less warm. On Syntagma square, banners read "Merkel out, Greece is not your colony" and "This is not a European Union, it's slavery."

Merkel tries to calm uproar over eurozone plans

"We don't want her here. Merkel go home!," said Maria Dimitriou, a 40-year-old unemployed woman who travelled to Athens from southern Greece to protest. "They've turned our lives into hell." 

Many of Europe's leading politicians have avoided official travel to Greece and the risk of a hostile reception, as the debt-saddled country struggled to keep up with commitments needed to guarantee rescue loan payments and long-term euro membership. 

Greece's respected Kathimerini daily said Tuesday that "no foreign leader should be afraid to come here." 

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"Extreme behavior, violence, and exaggerated comments by politicians on TV can achieve nothing to help the unemployed or pensioners and just place the country in a position where it looks bad whatever it does," an editorial said. "Today's visit is crucial and historic. Let us all treat it accordingly." 

Reuters and The Associated Press contributed to this report

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Updated at 8:59 a.m. ET: ATHENS, Greece -- Demonstrators wearing helmets and gas masks and armed with sticks clashed with police in the Greek capital on Wednesday, as a general strike was held to protest the government’s austerity drive.

Riot police fought with the protesters wearing the black clothes favored by anarchist groups for about 45 minutes in the central Syntagma Square, letting off tear gas in an attempt to disperse the crowd.

The demonstrators let off flares and a tent in the center of the square advertising an air show was set on fire.

The anarchist group appeared to be trying to cause as much damage in the square as possible.

Yannis Behrakis / Reuters

A Molotov cocktail explodes beside riot police officers near Syntagma Square in Athens on Wednesday.

There were also violent clashes between anti-austerity protesters and riot police in Spain on Tuesday. Police there told The Associated Press that 38 people were arrested and 64 people injured when officers clashed with protesters demonstrating against cutbacks and tax hikes.

Several thousand people converged on the Spanish Parliament building in central Madrid where more than 1,000 riot police blocked off access to the building, forcing protesters to crowd nearby avenues. Police baton-charged protesters at the front of the march and some demonstrators broke down barricades and threw rocks and bottles, the AP said. Reuters reported that police fired rubber bullets.

Spain's economic crisis turns middle-class families into illegal squatters

In Greece, perhaps the country worst-affected by the crisis, workers walked off their jobs for the first general strike since a coalition government was formed in June. 

Pablo Blazquez Dominguez / Getty Images

Spanish riot police clash with protesters during demonstrations over the government's austerity policies near the Spanish parliament on Tuesday.

The Greek government is struggling to push through more punishing austerity measures demanded by the country’s creditors.

'Only the beginning'
Initially, Syntagma Square was peaceful as tens of thousands of protesters arrived to the sound of drums. There were many elderly and middle-aged people and mothers with children among the crowd.

The strike was called by the country's two biggest unions that represent half the workforce.

"We call on everyone to take part in the strike and resist the austerity measures that hurt Greek people and the economy," Despoina Spanou, of the ADEDY labor group, said.  "This strike is only the beginning in our fight."

'It is virtually impossible to find a job': Brain drain is new Greek tragedy

Much of the union's anger is directed at spending cuts worth nearly $15.55 billion over the next two years that Greece has promised the European Union and International Monetary Fund in an effort to unlock its next tranche of aid.

The bulk of those cuts are expected from slashing wages, pensions and welfare benefits, heaping a new wave of misery on Greeks who say repeated rounds of austerity have pushed them to the brink and failed to transform the country for the better.

A survey by the MRB polling agency last week showed that more than 90 percent of Greeks believe the planned cuts are unfair and burden the poor, with the vast majority expecting more austerity in coming years.

Joblessness strikes more young people in Europe's wealthy north

With Greece in its fifth year of recession and no light at the end of the austerity tunnel, analysts warn that Greek patience is wearing thin and a strong public backlash could tear apart the weak conservative-led coalition.

During the protests in Spain Tuesday, people chanted outside the parliament, "Let us in, we want to evict you.” 

Evictions have soared in Spain as thousands of people have defaulted on bank loans.

Daniel Ochoa De Olza / AP

Thousands of demonstrators march to the Spanish parliament on Tuesday.

Protesters said they were fed up with cuts to public salaries and health and education. They are also angry that the state has poured funds into crumbled banks while it is cutting social benefits.

PhotoBlog: Spain prepares more austerity, protesters clash with police

"My annual salary has dropped by 8000 euros and if it falls much further I won't be able to make ends meet," Luis Rodriguez, 36, a firefighter who joined the protest, told Reuters. He said he is considering leaving Spain to find a better quality of life.

"We're protesting against the cuts. I've had to give up my apartment," said Ondina, a 30-year-old fine arts graduate who is without a job. She said she can't survive on an unemployment benefit of $340 a month.

Spain's 'Robin Hood' mayor on march, sparks outrage after supermarket heists

With this year's budget deficit target looking untenable, the conservative government is now looking at such things as cuts in inflation-linked pensions, taxes on stock transactions, "green taxes" on emissions or eliminating tax breaks.

Spain, also badly hit by the euro zone debt crisis, has been hit by a second recession since 2009 that has put one in four workers out of a job.

The Associated Press and Reuters contributed to this report.

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Editor's note: This article was corrected following publication to reflect the country Jean-Claude Juncker represents and add the first name of the German finance minister.

After a short, late-summer break, German officials are set to tighten the screws again on Greece, boosting the prospects that Athens would exit the eurozone and cause a painful shock to the global economy.

In the latest round of talks this week in Berlin, Greek Prime Minister Antonis Samaras is expected to lobby for a two-year extension of deeper spending cuts and tax increases when he meets with German Chancellor Angela Merkel, French President Francois Hollande and Luxembourg Prime Minister Jean-Claude Juncker, who heads the eurozone's finance ministers meetings.

German officials, though, made clear over the weekend that time has run out for the Greek government. Ruling out another Greek bailout, German Finance Minister Wolfgang Schaeuble said Sunday that Athens will just have to deal with the economic pain.

“It can’t be helped -- we can’t make yet another new (bailout) program,” Schaeuble told a public meeting in Berlin. “There are limits.”

But multiple rounds of budget cuts have left Greek officials with limited choices of their own. After two years of contraction, Greece’s economy is shrinking by more than 6 percent a year. Previous rounds of budget cuts have sparked massive, sometimes violent, demonstrations and upended the careers of the politicians who enacted them.

The Greek government doesn’t have the money to repay a massive a pile of debt coming due before year-end. Under the latest bailout deal, set up by the European Union and International Monetary Fund, Greek officials have to come up with 11.5 billion euros ($14 billion) of budget cuts over the next two years. Those cuts alone represent more than 5 percent of the country's falling gross domestic product.

To ease the pain of further cuts, Athens wants two more years to cut its budget deficit to below 3 percent of GDP, from 9.3 percent expected this year. But more time means more money. Extending Greece's bailout package by two years would cost another 20-50 billion euros ($24 billion to $60 billion) on top of the 130 billion euros ($157 billion) already paid or committed, according to estimates by some eurozone officials and economists.

But the German public is in no mood to send more of their savings to Athens after Greece has shown little to no progress in reviving its economy and as even Germany's growth has slowed. As Europe's largest economy -- accounting for roughly 30 percent of the eurozone's gross domestic product -- German popular support is critical for any Greek aid package.   

"I have always said that we can help the Greeks, but we cannot responsibly throw money into a bottomless pit," said Schauble, reflecting a widely-felt sentiment among German voters.

Now, after dozens of summits and repeated failed bailout plans, German officials have apparently concluded that the time of reckoning has arrived for eurozone countries that spent too freely and took on too much debt, according to Michael Crofton, CEO of Philadelphia Trust Co.

“They’re going to stand tough on the euro,” he told CNBC. “If you don’t pay the piper, if you don’t do what you’ve said you’re doing to do, if you don’t cut back on your budgets and impose austerity on your economies, then you’re going to be gone.”

Greece’s departure from the common currency, once unthinkable, may be near.

It would almost certainly force Athens to default on a large portion of its euro debt, which now totals roughly 160 percent of its annual economic output. European governments and banks, which own roughly two thirds of that debt, would likely have write off much of it.

With each failed attempt at finding a workable solution, Greece’s hold on eurozone membership has weakened. Lately, European officials have been doing more than just thinking about Greece’s departure from the common currency.

Bracing for the prospect, Europe’s central bank has begun contingency plans for the possible financial shock if Greece is forced out. Under the plan, reported over the weekend by Germany's weekly Spiegel magazine, the ECB would set up what amounts to a debt firewall, buying up bonds of other struggling eurozone countries like Spain and Italy, if interest rates on those bonds rose above set thresholds.

Such a move could discourage speculators from pushing rates to levels that would inflict pain on larger economies, helping to contain the prospect of a debt “contagion” spreading to Europe’s core. Central bankers have also been considering some form of bank deposit insurance to stem panic withdrawals by individuals and small businesses.

“I think we’re quite well prepared for a Greek exit,” said Chris Watling, CEO of Longview Economics. “This is something European leaders have been thinking about for two years. The bottom line is the Greek numbers arent huge. So I think it’s wholly containable at this stage."

Containable, perhaps, but it won't be a totally painless operation for the financial markets and banking systems, according to a top European Central Bank official.

"A withdrawal by Greece would be manageable," Joerg Asmussen told two German newspapers over the weekend. But "a withdrawal would not be as orderly as some imagine. It would be connected with lower growth and higher unemployment, and very expensive. In Greece, in the whole of Europe and in Germany too."