Nawaf al-Fares, the former Syrian ambassador to Iraq, told CNN in Qatar Sunday that Assad and his regime knew their time was up and were buying time by battling the stubborn insurgency.
"They are trapped," said Fares, who recently defected. "They committed crimes and they entered into a war of blood. And they are aware that they are going to pay for it. They are just buying time. Maybe they will get a chance to escape."
Al-Fares said he did not expect the Assad regime to give up power willingly.
The BBC reported there was heavy fighting in suburban Damascus Sunday as the military reportedly used tanks and mortars in an attempt to drive back the rebel fighters.
Hicham Hassan, a spokesman for the International Committee of the Red Cross, said the organization now regards the Syrian situation as a "non-international armed conflict," which the BBC noted is the technical term for civil war. The Red Cross monitors whether warring parties adhere to the provisions of the Geneva Convention.
"What matters is that international humanitarian law applies wherever hostilities between government forces and opposition groups are taking place across the country," he said.
The Syrian Network for Human Rights & Damascus Center for Human Rights Studies said they had documented 95 casualties across Syria Sunday. The death toll was unconfirmed.
Meanwhile, the Syrian government was denying accusations Sunday of a military massacre of anti-government rebels in the town of Tremseh.
Responding to claims that more than 200 people were shot and shelled by tanks in the town Thursday, Syrian Foreign Ministry spokesman Jihad Makdissi said what happened "was a military operation and not a massacre," CNN reported.
He denied allegations by rebels and observers the town came under siege.
"It is quite absurd that there are some media outlets who were spreading rumors that the Syrian military dispatched 150 tanks in such a small area," Makdissi said.
The government said the real death toll was 37, the BBC said.