French foreign affairs minister Jean-Marc Ayrault called on Tuesday for an immediate United Nations Security Council meeting to discuss the situation in the Syrian city of Aleppo, which has been devastated by fighting.
"More than ever before, we need to urgently put in place means to end the hostilities and to allow humanitarian aid to get through unhindered," Ayrault said in a statement.
A French diplomatic source added that Ayrault and his German counterpart would discuss Aleppo with Russian foreign minister Sergei Lavrov on the sidelines of a meeting in Minsk on Tuesday, at which leading European foreign ministers will discuss plans for implementing a ceasefire agreement for eastern Ukraine.
The Syrian army and its allies announced the capture of a large swathe of eastern Aleppo from rebels on Monday in an accelerating attack that threatens to crush the opposition in its most important urban stronghold.
Capturing eastern Aleppo would be the biggest victory for President Bashar al-Assad since the start of the uprising against him in 2011, restoring his control over the whole city apart from a Kurdish-held area that has not fought against him.
For Assad, taking back Aleppo would shore up his grip over the main population centers of western Syria where he and his allies have focused their firepower while much of the rest of the country remains outside their control.
France, a key backer of the Syrian opposition, is due to convene a meeting of countries opposed to Assad, including the United States, Saudi Arabia and Turkey, in December.