SANA via AFP - Getty Images
A handout picture released Tuesday by the official Syrian Arab News Agency shows Syrian President Bashar Assad, right, meeting with Saeed Jalili, a top aide to Iran's supreme leader Ayatollah Ali Khamenei, in Damascus.
Updated at 8:31 p.m. ET: As Syrian President Bashar Assad appeared on television for the first time in two weeks on Tuesday, U.S. Secretary of State Hillary Clinton said that the high-profile defection of the Syrian prime minister increased the urgency of planning for the ouster of Assad's regime.
In South Africa's capital, Pretoria, Clinton said the United States and other countries needed to make sure that Syrian state institutions remain intact once Assad loses his grip on power.
"The intensity of the fighting in Aleppo, the defections, really point out how imperative it is that we come together and work toward a good transition plan," Clinton said.
"I do think we can begin talking about planning for what happens next: the day after the regime does fall. I am not going to put a timeline on it, I can't possibly predict it, but I know it's going to happen as do most observers around the world," Clinton said.
Clinton also warned against "proxies or terrorist fighters" being sent in to join the 17-month-old conflict.
The escalating war in Syria has increasingly divided the region along its sectarian faultline, pitting the mainly-Sunni rebels, who are backed by regional Sunni-led powers Turkey and the Gulf Arab states, against Assad's government that is backed by Shiite Iran.
In a possible sign of increasing American pressure on Assad’s government, Clinton's remarks come a day after three U.S. senators warned about the risks of American failure to provide assistance to Syrian opposition fighters.
Clinton also spoke a day after the defection of Prime Minister Riyad Hijab, the latest in a string of high-level departures from the Assad regime.
Assad appeared on Syrian state TV on Tuesday meeting with Iran's Supreme National Security Council in Damascus.
Assad's absence had fueled rumors about his health, including a hoax Twitter message Monday that quoted Russia's ambassador to Damascus as saying Assad might have been killed.
Russian officials quickly denied the report.
In the week after a July 18 bombing that killed four members of his inner circle, Assad was shown twice in silent footage on television, swearing in a new defense minister and meeting military officials.
People resisting the army of President Bashar Assad in northern Syria cope with loss and prepare for fighting.
During Tuesday's Damascus meeting, Saeed Jalili, head of Iran's Supreme National Security Council, said Iran would not let its close partnership with the Syrian leadership to be shaken by the uprising or external foes.
"Iran will not allow the axis of resistance, of which it considers Syria to be an essential part, to be broken in any way," Syrian television quoted Jalili as saying.
The "axis of resistance" refers to Shiite Iran's anti-Israel alliance with Syria's rulers - from the Alawite faith which is an offshoot of Shiite Islam - and the Lebanese Shiite militant group Hezbollah, which fought a month-long war with Israel in 2006, with Iranian and Syrian support.
Damascus and Tehran have held Sunni Muslim Gulf Arab states and Turkey, all allies of the United States and European powers, responsible for the bloodshed in Syria by supporting the overwhelmingly Sunni Muslim rebels. Western powers sympathetic to the rebels are concerned that anti-Western Sunni Islamists could benefit from a victory for the anti-Assad forces.
Iran's Fars news agency said Jalili told Assad that Iran was prepared to provide humanitarian aid to Syria.
As estimated 18,000 people have been killed in the Syrian conflict, as rebels battle government forces in an attempt to wrest control from the Assad family's four-decade grip on power.
On a fence-mending visit to Turkey, Iranian Foreign Minister Ali Akbar Salehi said he wanted to work with Ankara to resolve the crisis. Turkish Prime Minister Tayyip Erdogan described as "worrying" a comment on Monday by Tehran's top general, who blamed Turkey, Saudi Arabia and Qatar for bloodshed in Syria.
Iran has expressed fears for more than 40 Iranians it says are religious pilgrims kidnapped by rebels from a bus in Damascus while visiting Shiite shrines. Salehi wrote to U.N. Secretary-General Ban Ki-moon seeking his help to free them.
Rebels say they suspect the captives were troops sent to help Assad. A rebel spokesman in the Damascus area said on Monday three of the Iranians had been killed by government shelling. He initially said the rest would be executed if the shelling did not stop but later said they were being questioned.
At least 262 al-Qaida militants are now operating in the border area between Turkey and Syria and rebels say another group of fighters are living in a tented camp just outside Aleppo, Syria's largest city. NBC's Richard Engel reports.
Fighting rages in Aleppo
On Tuesday, rebels trying to fight off an army offensive in Aleppo said they were running low on ammunition as government forces encircled their stronghold at the southern entrance to the country's biggest city.
Assad has reinforced his troops in preparation for an assault to recapture rebel-held districts of Aleppo after repelling fighters from most of Damascus.
"The Syrian army is trying to encircle us from two sides of Salaheddine," said Sheikh Tawfiq, one of the rebel commanders, referring to the southwestern neighborhood which has seen heavy fighting over the last week.
Mortar fire and tank shells exploded across the district early Tuesday, forcing rebel fighters to take cover in crumbling buildings and rubble-strewn alleyways.
Tanks have entered parts of Salaheddine and army snipers, using the cover of heavy bombardment, deployed on rooftops, hindering rebel movements.
Machine guns operated by motorcycle brakes? Get a glimpse at the rebels fighting against Assad's forces in Syria's mountainous Jabal al-Zawiya area.
Another rebel commander, Abu Ali, said snipers at the main Saleheddine roundabout were preventing the rebels from bringing in reinforcements and supplies. He said five of his fighters were killed on Monday and 20 wounded.
But rebels said they were still holding the main streets of Salaheddine which have been the frontline of their clashes with Assad's forces.
A fighter jet pounded targets in the eastern districts of Aleppo and artillery shelling could be heard in the early morning, an activist in Aleppo said.
"Two families, about 14 people in total, were believed killed when a shell hit their home and it collapsed this morning," the activist said. The house was one street away from a school being used by rebels, he said.
Reuters, The Associated Press and NBC News' staff contributed to this report.
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