An evacuation of rebels and civilians from the small part of Aleppo still under their control has been delayed for unknown reasons.

Buses had been due to start taking people out of the city at the start of a ceasefire at 3am GMT, but the Syrian Observatory for Human Rights said nobody had left an hour later.

A witness said none of the buses brought to evacuate rebels and civilians had moved into Aleppo's eastern districts by 4.15am GMT, Reuters news agency reports.

The evacuation comes as insults were exchanged at a United Nations emergency session which was convened over reports of government troops and allies killing more than 80 civilians "on the spot".

Russia wants us dead: A last message from Aleppo

Russia's ambassador to the UN told the meeting that "military actions in eastern Aleppo are over", while Syria's ambassador hailed the "liberation" of the city.


President Bashar al Assad's forces, backed by Russia and other groups, have recaptured the vast majority of eastern Aleppo in recent days.

Image: Some residents have been leaving the east for government-held areas

According to state TV, they now hold 98% of neighbourhoods previously occupied by the rebels.

An estimated 1,500 fighters and tens of thousands of civilians remain, including more than 100 unaccompanied children who were earlier inside a building under heavy attack.

The UN human rights office said it had reports of pro-government forces killing at least 82 civilians in eastern Aleppo, including 11 women and 13 children in four different neighbourhoods.

+100,000 civilians are packed into a tiny area. Bombing + shelling relentless. Casualties unimaginable. Bodies lie where they fell. — The White Helmets (@SyriaCivilDef) December 13, 2016

"The reports we had are of people being shot in the street trying to flee and shot in their homes," UN humanitarian spokesman Jens Laerke told reporters.

He said the situation appeared to be "a complete meltdown of humanity".

:: Aleppo under siege: A timeline

Aleppo: Killing Hope - A Sky News special report

The White Helmets, the volunteer search and rescue force, tweeted: "+100,000 civilians are packed into a tiny area. Bombing + shelling relentless. Casualties unimaginable. Bodies lie where they fell."

Amid the reports, the House of Commons also held its own emergency debate.

Image: Aleppo then and now: Umayyad Mosque, 2013... Image: ... and the Umayyad Mosque in 2010 Image: The Old City seen from Aleppo's historic citadel, 2009 Image: An image taken with a drone shows the Old City of Aleppo and the citadel, 2016 Image: An antique shop in al Jdeideh neighbourhood, 2009 Image: Men salvage belongings from their damaged shops that were hit by airstrikes, 2016 Image: The Shahba Mall, one of the largest commercial shopping centres in Syria, 2009 Image: The mall after airstrikes by forces loyal to Assad in 2014. Continue through for more pictures of Aleppo before and after the destruction /

Former chancellor George Osborne told MPs they had missed a chance to stop the onslaught in Aleppo when a vote on military action was narrowly defeated in 2013.

He said they were "deceiving" themselves if they believed they did not bear some responsibility for the "terrible tragedy".