United Nations peace envoy Lakhdar Brahimi hopes to persuade Syria’s President Bashar al-Assad to comply with a four-day truce during the Muslim holiday marking the Hajj, which begins Oct. 25, but many in the opposition remain skeptical about his plan.  

Brahimi, who arrived in the capital Damascus on Friday afternoon, will meet Foreign Minister Walid al-Moualem on Saturday morning, said the U.N. spokesman in Damascus, Khaled al-Masri. He did not say whether the envoy would meet Assad.

"We will talk about the ceasefire and the Syrian issue in general. It is important to decrease the violence - we will talk with the government and political parties and civil society about the Syrian issue," Brahimi told reporters upon arrival.

The violence showed no sign of abating, with opposition activists reporting heavy street clashes in Aleppo, Syria's biggest city, and intensified army bombing of towns along the strategic north-south highway. U.N. Secretary-General Ban Ki-moon and Arab League chief Nabil Elaraby backed a ceasefire. "The longer the violence lasts, the more difficult it will be to find a political solution and rebuild Syria," they said in a joint statement.

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Turkish Foreign Minister Ahmet Davutoglu called for all sides to observe the three- or four-day ceasefire.

"It is important that the Syrian regime, which bombards its own people with fighter planes and helicopters, halts these attacks immediately and unconditionally," Davutoglu said in Ankara.

Iran also backed the ceasefire call but added that the main problem in Syria was foreign interference - a reference to support for the rebels by Gulf Arab states, the United Sates and other Western powers, and Turkey.

"We consider the establishment of an immediate ceasefire an important step in helping the Syrian people," Iranian Deputy Foreign Minister Hossein Amir Abdullahian said, as quoted by Mehr news agency.

"Syria has taken important steps against terrorism and foreign interference and is pursuing political reforms and the security of the country."

Most opposition forces doubt Syria will comply with what they see as another toothless initiative. The largest opposition group, the Syrian National Council, has thrown its support behind the initiative but will hold the Syrian government responsible for any violation. 

“The last time [a cease fire was agreed upon], the Syrians [who support Assad] violated it the first day. I hope this time they will respect it,” says Khaled Khoja, council representative and spokesman in Turkey. “I hope this time they will accept it, allow people to express their ideas peacefully, release prisoners and withdraw their forces from cities.”

Although Khoja says the Free Syrian Army, an umbrella organization for defected soldiers and armed opposition, has conditionally accepted the truce, its fighters will respond if attacked first by Syrian government forces. Khoja, like many in the opposition, worries that the initiative will fail because there is no penalty to compel the regime to observe the ceasefire.   

Syrian helicopter reportedly downed by rebels over Idlib

“There must be a mechanism in order to make the Syrian regime comply. If there is no mechanism, the Syrian regime will continue to do the same.”

Rafif Jouejati, the Washington, D.C. based spokeswoman for the Local Coordination Committees, the largest activist network inside Syria, believes the truce is destined to fail.

“It is a feeble attempt by the international community that has no timeline, no consequences for failure to observe it, no consequences for continued bombardment. Since there are no consequences, any plan will fail and [Assad] will continue to kill civilians. It carries the same weight as a U.N. condemnation," she said.

"Unless there are actual consequences, it is meaningless. I have relayed messages to Brahimi from the protesters: ‘Welcome to Syria on your mission impossible. Why didn’t you send Tom Cruise?’ It is an insult to the people who go out everyday and brave the bombing and bullets.”

Syrian government forces strike rebel held towns

Jouejati said this was the fourth attempt at brokering a ceasefire deal. “Assad has proven he is not going to look for political solutions. He has confirmed it through word and deed and will continue his security solution.” 

A Britain-based monitoring group, the Syrian Observatory for Human Rights, doubts Brahimi’s ability to influence armed elements, whether they're on the opposition or government side. Brahimi cannot control Jebhat al Nusri, a jihadist militia, said director Rami Abdulrahman.  "He cannot control what is happening on the ground," Abdulrahman said. "He doesn’t know how many Syrian troops are on the ground.”

More than 30,000 people have been killed over 19 months in the intensifying conflict.

More weapons in Syria could trigger 'all-out war'

There is little agreement among the many armed rebel militias who are temporarily unified by the desire to topple Assad. Although the Free Syrian Army reportedly supports the truce, a senior commander in Daraa, a Syrian city on the border with Jordan and the starting point of the revolution, told the British Guardian newspaper, “Brahimi’s proposal for a truce is stillborn. 

“His project does not have any hope. Even if [exiled FSA leader] Riad al Assad accepts the truce, we will not. We will continue to fight," Staff Col. Ahmad Fahd al-Nimah, commander of the military council in Daraa, told the Guardian. "We represent those fighting on the ground in Syria. No one outside Syria can tell us what to do.” 

An activist reached by phone in the same city told NBC News the people in the streets of Syria do not accept the ceasefire. Da’il, who gives only his first name for security purposes, believes the regime will use the ceasefire to fortify military positions. 

“Before, when the Arab League and U.N. sent in peacekeeping observers, peaceful protesters were still being shot at. How can there be a ceasefire now, when there is nobody on the ground to observe it? No way will it work. Right now there is a roadblock with a sniper in front of me. If I walk out I will get shot. There is no way to stop the fighting. It is going on all the time,” he said. 

Da’il went on to express the public’s cynicism toward the initiative: “There is a local saying here: If somebody tries something and fails, he is crazy if he tries the same thing again.” 

Reuters contributed to this report.

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Amnesty International released satellite images Wednesday which appeared to show the extent of artillery bombardment in the Syrian city of Aleppo where rebels are struggling to fight off an offensive by forces loyal to President Bashar Assad.

The international human rights group said both sides fighting in Aleppo, the country's largest city, might be held criminally accountable for their failure to protect civilians.

It said the images, obtained from commercial satellites over the July 23 - Aug. 1 period, showed more than 600 craters, probably from artillery shelling, dotting Aleppo's surrounding areas. The craters were represented with yellow dots in the images.

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One photo, from July 31, showed craters next to what looked like a residential housing complex in the nearby town of Anadan, Amnesty said.

'Atrocities'
The organization expressed concern about the deployment of heavy weaponry in residential parts of Aleppo. 

"Amnesty International is sending a clear message to both sides in the fighting: Any attacks against civilians will be clearly documented so that those responsible can be held accountable," said Christoph Koettl, emergency response manager for Amnesty International USA.

"Turning Syria's most populous city into a battlefield will have devastating consequences for civilians. The atrocities in Syria are mounting already," Koettl said.

Syria's Assad appears on TV for 1st time in 2 weeks

"The Syrian military and the opposition fighters must both adhere to international humanitarian law, which strictly forbids the use of tactics and weapons that fail to distinguish between military and civilian targets," he added.

The popular uprising against Assad's rule erupted 17 months ago. Activists say an estimated 20,000 people have been killed in the unrest, Reuters said.

Assad has been reinforcing troops in preparation for an assault to recapture rebel-held districts of Aleppo after repelling fighters from most of the capital Damascus.  The fighting on the ground has been fierce.

On Wednesday, rebels abandoned at least one position in a battered district where battles have raged for days, Reuters reported.

"We have retreated, get out of here," a lone rebel fighter yelled at Reuters journalists as they arrived Wednesday in the Salaheddine district. Nearby checkpoints that had been manned by rebel fighters for the last week had disappeared.

NBC's Ayman Mohyeldin answers your questions about Syria

A Syrian government security source told Lebanon's Al-Manar television that its forces were now in control of the district, but an opposition watchdog, the Syrian Observatory for Human Rights, said clashes were still occurring there, Reuters reported.

Russian general killed?
Meanwhile, a Syrian rebel group said Wednesday it had killed a Russian general working as an adviser to Syria's Ministry of Defense in an operation on the outskirts of the capital Damascus.

A video statement from a group calling itself the "Hawks Special Operations Battalion ... a division of the Military Leadership of Damascus City and Province," gave the name of the general as Vladimir Petrovich Kochyev. The video, sent to Reuters, showed what the rebels said was a copy of his ID, as issued by the Syrian military.

The operation occurred in the Ghouta region, west of Damascus, Reuters said.

But Russian news agencies quoted Moscow's defense ministry as calling the report a "bald-faced lie." The general appeared in person, Itar-Tass said.

"I want to confirm that I am alive and well," the news agency quoted him as saying, according to Reuters.

US makes plans to keep post-Assad Syria intact

The same group claimed responsibility for the assassination of four of Assad's top lieutenants in Damascus last month.

The rebel's main armed group the Free Syrian Army called the purported killing of the Russian general, along his private translator, evidence that Russia was involved in the "humanitarian crimes" against Syrians, according to pan-Arab news channel al-Arabiya.
"We warn all the snakes to go back to their dens whether it is Russia, Iran and Iraq or Lebanon," a Free Syrian Army officer said in the video, al-Arabiya reported.

Russia, along with Iran, China and Lebanese militant group Hezbollah, have opposed foreign intervention. Russia and China have blocked three tries to impose sanctions against Damascus in the United Nations Security Council.

Official: Syria PM defects to anti-Assad oppositon

As Assad's forces battle for Aleppo, there has been no let-up in fighting elsewhere in Syria. More than 240 people were killed across the country on Tuesday, 40 of them in the central city of Homs, the Syrian Observatory for Human Rights told Reuters.

Reuters contributed to this report.

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Updated at 4 p.m. ET:

The United States has "grave concerns" about the situation in Syria, the State Department said Thursday, as President Bashar Assad's forces withdrew from many towns and villages and focused their firepower on the key city of Aleppo.

"This is the concern, that we will see a massacre in Aleppo, and that's what the regime appears to be lining up for," said spokeswoman Victoria Nuland.

Citing "columns of tanks" outside the city, Nuland said the Syrian military "seem(s) to be massing for an attack." She called the use of fixed-wing aircraft in addition to helicopter gunships a "serious escalation in this conflict."

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"It could be a humanitarian disaster for the people of Aleppo," NBC News' Richard Engel reported from northern Syria. "It also means the Syrian troops are forced to make trade-offs. They don't have enough loyal troops to make the offensive against Aleppo and hold these rural areas."

Nuland said Assad's regime was "increasingly losing control of its territory, that there are swaths of the country that are no longer under the control of the regime, that his tactics are increasingly violent, increasingly desperate as that happens."

Myth vs. truth in the Syrian conflict

Military experts believe an overstretched Syrian army is pulling back to concentrate on fighting insurgents in Aleppo and Damascus, important power centers for the government, while leaving outlying areas in the hands of rebels. Assad's forces have launched massive counterattacks in both cities.

Meanwhile, opposition activists said thousands of troops had withdrawn with their tanks and armored vehicles from Idlib province near the Turkish border and were heading toward Aleppo. Rebels attacked the rear of the troops withdrawing from the north, activist Abdelrahman Bakran told Reuters from the area.

Fierce clashes raged in the early hours in Aleppo itself, and an activist said rebels now controlled half of the city, a claim that could not be independently verified. 

Council on Foreign Relations: What you need to know about the Syrian crisis

"There was shelling this morning on the Salaheddine and Mashhad districts," Aleppo activist Abu Hisham told Reuters. "Now it stopped, but helicopters are buzzing overhead." 

Activists said 24 people were killed in fighting in and around Aleppo on Wednesday, swelling a national death toll of about 18,000 since the revolt against Assad began 16 months ago. 

'Terrorists are suffering terrible losses'
State-run Syrian television painted a more favorable picture, saying government troops were imposing security and stability in and around Aleppo.

"The terrorists are suffering terrible losses. Groups of them are throwing their weapons away and giving themselves up. Others are fleeing for the Turkish border," the television report said. 

Photos: The battle for Aleppo

Engel and other journalists have repeatedly observed government troops retreating from "secondary towns" so they can fight opposition forces in the capital Damascus and now Aleppo, leaving vast swathes of the countryside under rebel control. 

"When government forces pull out of a place they lose control and immediately rebel flags go up and rebels hold celebrations," Engel said. "Those celebrations have been attacked so now the rebels are deciding not to hold celebrations because they're noisy, they have lights and they're easy to target."

Total war: Syria sends armored column to Aleppo

Meanwhile, north of Aleppo, the town of Azaz has been almost completely destroyed by heavy fighting, Reuters reported. Burned-out armored personnel carriers sat on the roads where rebels hit them with rocket-propelled grenades. Bullet casings were scattered everywhere. 

In another key development, neighbor Turkey was not allowing goods or people to pass over the Bab al-Hawa border crossing after rebels took base near Aleppo over the weekend, Engel said. 

"Maybe they're concerned about there being too many rebels or refugees crossing," he said. "There may also be concern that the Turks may be losing control of security in sourthern Turkey."

Fighting in and around Aleppo is expected to prompt an exodus across the Turkish border, where some Syrian refugees are already complaining about poor conditions and have clashed with riot police in disputes over food. 

"There is not enough food. They have broken our hearts, the Turks. Why are they doing this to us?" a sobbing woman named Umm Omar, with her four children huddled next to her in a camp near the border, told Reuters.

Photo Blog: Who are the Syrian rebels?

Rebels also took the Bab al-Salam border crossing with Turkey over the weekend.

Artillery and rockets
Further south, Syrian forces used artillery and fired rockets on Wednesday on the northern Damascus suburb of al-Tel in an attempt to seize it from rebels, forcing hundreds of families to flee, residents and opposition activists said. 

"Military helicopters are flying now over the town. People were awakened by the sound of explosions and are running away," Rafe Alam, one of the activists, told Reuters by phone from a hill overlooking Tel. "Electricity and telephones have been cut off." 

Opposition sources also reported helicopters and machine guns were firing on the neighborhood of Hajar al-Aswad. The slum lies on the southern outskirts of the capital and has been a haven for rebels sneaking into Damascus from the suburbs. 

NBC News' Kari Huus and F. Brinley Bruton and Reuters contributed to this report.

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News Analysis

NORTHERN SYRIA – The rebels call this Free Syria. 

I am writing from a village that was occupied by Syrian soldiers four hours ago – the tracks of retreating tanks are freshly pressed into the pavement.

Grape vines hang in the small garden of the two-room stone house I’m in.  There’s no electricity, but there is fresh water from rural wells.  Bullet holes – some as small as grapes, others big as oranges – pierce the house’s walls. 

Still, the people in this village are celebrating.

“Free Syrian army! God protect them!” they shout, index and middle fingers splayed into a “v” for victory. 

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The 200 Syrian troops who’d been shelling this village of 8,000 olive and walnut farmers withdrew under fire Wednesday night.  Women and children who had been hiding in other villages within walking distance stream in, loaded with vegetables and yogurt. 

The returning families sift through the debris of their homes.  The villagers find that many houses were burned by Syrian troops.  The Syrian army appears to have carried out a deliberate scorched-earth campaign here. 

The troops burned every home with a son, son-in-law or even cousin among the rebels, residents tell us.  There can be little doubt that this is government policy (and what appears to be a war crime) because the same thing has happening in every village we’ve visited. 

A man who returned to this village had a leg cut off under torture by Syrian forces.  He’s 74 years old.

Another man who escaped Damascus five days ago says the fighting in the capital is now so bad that President Bashar Assad isn’t sending ground forces into rebel neighborhoods anymore and is only shelling them from afar.  He doesn’t want to send foot patrols out of fear the troops will defect, people say.

The regime is on the ropes.  

Total war: Syria sends armored column to Aleppo

The Assad goverment is concentrating its firepower on big cities like Damascus and Aleppo.  Government troops left this village last night to join the attack on Aleppo.  But the rebels, and Syria, need urgent help to prevent huge losses of life, both among fighters and civilians – Sunni, Allawite and Christian.

Many myths circulate in Washington and in the media about the Syrian opposition and the fighting in this country.   From what I’ve seen traveling with the rebels, many of the commonly accepted ‘truths’ seem to be incorrect.  After all, the first casualty of war is the truth.

Myth: The rebels are getting weapons and money from abroad and will soon finish off Bashar’s army on their own. 

View from the ground: The rebels are fighting with almost nothing.  I was with a rebel commander yesterday who has 48 men.  Only 15 of his fighters have any weapons.  He has almost no ammunition.  He has one anti-aircraft gun, but not a single bullet for it. 

The rebels don’t have enough gasoline to put in their vehicles.  The gas they can find costs the equivalent of $8 a gallon.  Food is plentiful, and so is water.  But weapons and ammunition are in desperately short supply.  Another unit I have seen is armed with homemade bombs that they try to fire from cardboard tubes.  

The rebels are now starting to get Motorola radios.  They are new and coming from Turkey.  Washington has recently said it will help private non-lethal aid, including communications equipment.  But the radios are of little use.  Communications have never been the rebels’ main problem.  In fact, the rebels coordinate and communicate effectively already.  They use  both the new Motorola radios and local Syrian cellphones.  The cellphones can be monitored by Syrian intelligence, but the rebels’ strategy has been to overwhelm the Syrian government’s ability to listen. 

Because the rebels – commanders and foot soldiers – all use cellphones and landlines, there are tens or thousands of conversations going on at any one time.  The rebels speak vaguely and in primitive codes.  It seems unlikely that Syrian forces are able to keep track of such a high volume of calls and effectively act on them.  The rebels do appreciate the radios and use them, but they are a secondary priority. 

Syria: What you need to know about the crisis from the CFR.org

What the rebels say they truly need are arms that can pierce Syrian armored vehicles.  They need 12.7 anti-aircraft ammunition.  They say they need 14.5 ‘doshka’ rounds.   They need armor penetrating RPGS.  They need 60mm and 120mm mortars.  They need 7.62 rounds.  These are what commanders ask for whenever I meet them.  These are what every rebel wants.

Myth: The rebels are disorganized, have no leaders and are rife with infighting.

View from the ground: The rebels have no central leadership.  They do not have a single commander.  The rebels generally do not recognize the leaders of the Syrian opposition in exile in Turkey and Europe.  But on the ground here in Syria the rebels are well organized.   Their structure is more organic than hierarchical, less like a pyramid than a bungle of grapes, with individual cells joined together by a common cause.  The rebel cells coordinate well with each other.  Since weapons are in such short supply, all rebel military operations are collective efforts.  In the town where I am, there are no fewer than five different rebel commands.  They respect each other.  They trade weapons and fighters.  Some units are more Islamic in their politics, others are secular.  The differences in politics do not prevent their coordination.

Photo Blog: Who are the Syrian rebels?

Myth: The rebels are al-Qaida or at least infiltrated by al-Qaida.

View from the ground:  We have not seen evidence of a large al-Qaida presence.  This is not an al-Qaida fight.  In the last 24 hours we have met three rebel commanders.  One was an air-conditioner repairman before the war.  Another was a tomato and zucchini farmer.  The third grew grain and lentils.  One of the commanders considers himself an Islamist.  The other two are more secular. 

In total, the three commanders control about 1,500 men.  Not one of the commanders supports al-Qaida, nor have any of the dozens rebels have we have met.  There were reports that al-Qaida fighters had recently taken over the Baab al-Howa border crossing between Syria and Turkey.  There was a video that showed rebels carrying a suspicious-looking all black flag, similar to ones favored by al-Qaida.  We spoke with the rebel leader who carried the flag.  He said he has nothing to do with al-Qaida and the flag was an Islamic one.

Syrian forces launch air attacks on largest city

Al-Qaida’s presence may grow, however, without a quick end to this conflict.  The rebels need help.  Their men are dying.  Their homes are being burned.  As time goes on, the temptation to welcome help – even if offered from al-Qaida –will grow.  We have heard reports of foreign fighters coming to Syrian from Algeria and Saudi Arabia.  We have heard reports that al-Qaida is offering some rebel commanders money.  The longer this drags on, the more dangerous it will get.

Myth: The rebels want a NATO intervention

View from the ground: The rebels do not want American or European soldiers in Syria.  Many rebels do not specifically even want a no-fly-zone, although I suspect many would welcome it.  Mostly, they just want access to weapons. 

Myth: After Assad is toppled there will be ethnic cleansing of Allawite (a secretive Shiite sect) civilians by the Sunni majority. 

View from the ground: Syrians don’t want ethnic violence, but some may happen.  It’s already happening.  There have already been ethnically motivated massacres.  The longer the war continues the worse this will become.  Syria is not, however, Iraq. 

There are no U.S. troops in Syria trying to organize elections.  The U.S. presence and American missteps made ethnic violence in Iraq far worse than it would have been otherwise after Saddam Saddam Hussein's fall.  The Syrians are better suited to sort out their internal divisions than anyone else. 

A first? Helicopter gunships bombard Syrian capital

Allawites comprise about 10 percent of Syria’s 23 million people.  They are the government’s favored sect.  The Assad family is Allawite.  If Assad falls, there may be vendetta killings of some Allawites.  More than 17,000 Syrians have already been killed, which means 17,000 angry families.  It will be difficult to contain all that rage.  The longer the conflict continues, however, the more vengeance there will be.  If there are more large-scale massacres – if Aleppo is reduced to a smoldering pile like Homs – the aftermath could be much worse. 

But Syrians I have spoken to say they do not want a civil war.  They do not want to drive Allawites from the country.  Mostly, they want justice.  The rebels know exactly who they are looking for.  They have the names of Syrian government officers and militiamen responsible for massacres and torture.  They want to bring them to justice, but not to perpetrate more atrocities.  Syria needs help organizing a justice system to deal with the popular demands for retribution after the regime collapses. 

The conflict in Syria seems to be in its final stages, but how long this stage will last depends largely on what happens in the coming days and weeks and the amount of support the rebels receive. 

All indications are that Assad is going to fall.  But how many more Syrians need to go with him?

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Syria sent thousands of troops surging toward Aleppo in the early hours of Wednesday, where its forces have been pounding rebel fighters from the air, engulfing the country's largest city in total warfare to put down a revolt. 

"[President Bashar] Assad is fighting hard here because he has already lost control of nearly all the towns around Aleppo," NBC News' chief foreign correspondent Richard Engel said from the city's outskirts on Tuesday.

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Recent days have seen Syria's 16-month-old uprising transformed from an insurgency in remote provinces into a battle for control of the two main cities, Aleppo and the slightly smaller capital, Damascus, where fighting exploded last week. 

President Bashar Assad's forces have launched massive counter assaults in both cities. They appear to have beaten rebels back from neighborhoods in the capital and are turning toward Aleppo, a commercial hub in the north. 

Syrian forces fired artillery and rocket barrages early on Wednesday at the northern Damascus suburb of al-Tel in an attempt to seize the town from rebels, causing mass panic and forcing hundreds of families to flee the area, residents and opposition activists said. 

The 216th mechanized battalion headquartered near Tel started bombarding the town of about 100,000 people at 3:15 a.m. (8:15 p.m. ET Tuesday) and initial reports indicated residential apartment blocks were being hit, they said. 

Photos: Syrian forces launch air attacks in Aleppo

"Military helicopters are flying now over the town. People were awakened by the sound of explosions and are running away," Rafe Alam, one of the activists, said by phone from a hill overlooking Tel. "Electricity and telephones have been cut off." 

Jets firing?
Some residents said they believed the planes had dropped bombs, but others said booming sounds could have been caused by supersonic jets breaking the sound barrier. A correspondent for Britain's BBC television also said the jets had fired on parts of the city. 

Syrian forces launch air attacks on largest city

Assad's forces have occasionally launched airstrikes from fixed-wing jets on other cities during the uprising, but tend to rely on helicopters for airstrikes in urban areas. 

Opposition activists said thousands of troops had withdrawn with their tanks and armored vehicles from the strategic Jabal al-Zawiya highlands in Idlib province near the Turkish border and were headed toward Aleppo. 

Rebels attacked the rear of the troops withdrawing from the region at the villages of Orom al-Joz and Rami near the main Aleppo-Latakia road and at the village of al-Bara west of the Aleppo-Damascus highway, activist Abdelrahman Bakran said from the area. 

A first? Helicopter gunships bombard Syrian capital

"I heard at least 20 rockets fired, I think from helicopters, and also a lot of machine-gun fire," a resident near one of the areas being shelled, who asked to be identified only by his first name Omar, said by telephone. 

"Almost everyone has fled in panic, even my family. I have stayed to try to stop the looters; we hear they often come after an area is shelled." 

General speaks
Meanwhile, a Syrian former Brigadier-General spoke for the first time since defecting earlier in July.

In a statement broadcast Arabic news channel Al Arabiya, Manaf Tlas called on Syrians to unite.

"I speak to you as a defected member of the Syrian army, who refuses criminal violence … I speak to you as one of the sons of Syria," Tlas said.  He was believed to be speaking from Paris where he has family.

"Honorable Syrian army officers do not accept the criminal acts in Syria … Allow me to serve Syria after [President Bashar] al-Assad's era." he said. 

Tlas' defection was a significant blow to Assad and his government. While Tlas is from Syria's majority Sunni community -- Assad and much of his inner circle are Alawite, an offshoot of Shiite Islam -- he was reportedly part of the president's inner circle for many years. 

"We must all unite to serve Syria and promote stability in the country, rebuilding a free and democratic Syria," Al Arabiya quoted Tlas as saying. 

"Allow me to call on a united Syria," he added.

Tlas also said he did not blame those troops who have not defected, adding that "whatever mistakes made by some members of the Syrian Arab Army ... those honorable troops who have not partaken in the killing ... are the extension of the (rebel) Free Syrian Army."

Chemical weapons safe?
Also on Wednesday, Moscow said it had received "firm assurances" from Damascus that its Syrian chemical arsenal is "fully safeguarded," Russian Deputy Foreign Minister Gennady Gatilov told the state-owned Itar-Tass news agency. 

"We have received firm assurances from Damascus that the security of this arsenal is fully safeguarded," Gatilov told the agency in an interview. 

Syrian Foreign Ministry spokesman Jihad Makdissi acknowledged on Monday that the country had chemical weapons, and Western countries and Israel have expressed fears chemical weapons could fall into the hands of militant groups as Assad's authority erodes. 

Israel, which has publicly discussed military action to keep Syrian chemical arms or missiles out the hands of Assad's Lebanese militant allies Hezbollah, said there was no sign any such diversion had occurred. 

"At the moment, the entire non-conventional weapons system is under the full control of the regime," a senior Israeli defense official, Amos Gilad, told Israel Radio. 

Reuters contributed to this report.

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