France lashes at Russia over Syria; Aleppo mayor seeks EU help

French President Francois Hollande accused Russia on Thursday of reneging on its pledges in Syria, as the mayor of the besieged Syrian city of Aleppo appealed to Europe to send monitors to help ensure the safety of civilians.

"I have been talking constantly to Russia, and Russia makes commitments that it is not keeping. Now it is time for us to conclude a ceasefire," Hollande told reporters as he arrived in Brussels for a summit of European Union leaders.

"We can't leave women, men and children to suffer bombing, have their safety threatened, be taken by force and treated in such an undignified manner," he said. "The regimes that support (Syrian President) Bashar Assad will have to take responsibility for this extremely serious situation."

Outside EU headquarters, Aleppo Mayor Brita Hagi Hasan warned that 50,000 civilians in eastern Aleppo "are about to be victims of a general massacre."

Speaking through an interpreter, he called for "a courageous position from the European Union, a position of sending some forces to monitor the evacuation of civilians."

"We never asked any country to go to war ... we only ask to save civilians and secure some corridors for their evacuation," Hasan said.

Hasan said more than 800 wounded people in eastern Aleppo need evacuating urgently and over 5,000 others who are hurt should also leave.

Residents in eastern Aleppo started to board buses and ambulances Thursday as the long-awaited pullout from the last rebel enclave in the embattled Syrian city got underway.

The evacuation is part of a cease-fire deal reached this week to have the opposition surrender their last foothold in Aleppo to Syrian government control in the face of a devastating ground and air offensive by government forces.

Hundreds of Syrian civilians have been killed and tens of thousands displaced in the Russian-backed Syrian government campaign to retake Aleppo.

The EU has been largely sidelined during the conflict, and has chosen to focus its diplomatic efforts on securing a ceasefire, opening up humanitarian corridors for people to leave and lobbying leaders in the region to try to end to more than five years of war.

"I'm completely depressed about the situation in Aleppo, it's really tragic," said Austrian Chancellor Christian Kern.

Hasan was later invited into the EU summit, and sat alongside EU Council President Donald Tusk as he opened the meeting.

In private talks with Hasan, Tusk acknowledged that "the last thing your people in Aleppo need today is more words of sympathy."

"The only thing you need today is real and effective assistance," a visibly emotional Tusk said.