An AFP correspondent saw rescuers known as the "White Helmets" forced to abandon efforts to retrieve a wounded woman from the rubble of a collapsed home when air strikes resumed.

When they ventured back to the site, the woman was dead.

Talks for a deal between the regime and the armed groups controlling Ghouta appear to have stalled.

Russian Foreign Minister Sergei Lavrov said jihadist fighters in Ghouta had rejected an evacuation deal.

"A few days ago, our military in Syria suggested to the fighters that they withdraw peacefully from Eastern Ghouta, like the evacuation of fighters and their families that was organised in East Aleppo," he said.

The head of the defence committee in Russia's lower house of parliament said Thursday that more than 200 new types of weapons were tested as part of his country's military support to the regime of President Bashar al-Assad.

"It's not an accident that today they are coming to us from many directions to purchase our weapons, including countries that are not our allies," he said.