A Syrian government military offensive in Aleppo, backed by Russia and Iran, is over, Russia's UN envoy has said as the United States described the violence in the besieged city as "modern evil."
Ambassador Vitaly Churkin said on Tuesday that an agreement had been struck for rebels to evacuate the north-western city and civilians would be unharmed, despite western and UN accusations that civilians had been intentionally killed.
"Over the last hour we have received information that the military activities in east Aleppo have stopped, it has stopped," Mr Churkin told a heated UN Security Council meeting called by France and Britain. "The Syrian government has established control over east Aleppo."
The rout of rebels from their ever-shrinking territory in Aleppo sparked a mass flight of civilians and insurgents in bitter weather on Tuesday (local time), a crisis the United Nations said was a "complete meltdown of humanity" with civilians being shot dead.
By finally dousing the last embers of resistance burning in Aleppo, Syrian President Bashar al-Assad's military coalition of the army, Russian air power and Iran-backed militias will have delivered him his biggest battlefield victory of the war.
New Zealand's Permanent Representative to the United Nations, Gerard van Bohemen, has blasted Russia for refusing to let the UN get onto the ground in Aleppo.
"I was often asked by my colleagues 'What will be your Rwanda moment?' I think it's probably arrived," he said.
"Then, as now, there were credible reports coming in of atrocities being committed. Then as now there was someone at the table - a party to the conflict that had their own view."
Russian UN Ambassador Vitaly Churkin has told the UN Security Council that the Russian-backed Syrian Army's military operation in Aleppo will end "in the next few hours."
"All militants, together with members of their family and the injured, currently are going through agreed corridors in directions that they have chosen themselves voluntarily," Churkin said on Tuesday.
Rebel officials said fighting would end on Tuesday evening and insurgents and the civilians who have been trapped in the tiny pocket of territory they hold in Aleppo would leave the city for opposition-held areas of the countryside to the west.
US Ambassador to the United Nations, Samantha Power, told the council that the Syrian government and its allies Russia and Iran bore responsibility for killings of civilians in Aleppo.
Secretary-General Ban Ki-moon was briefing the Council at the request of Britain and France. A Syrian military source said the last rebel pocket could fall "at any moment".
"My latest information is that they indeed have an arrangement achieved on the ground that the fighters are going to leave the city," Churkin earlier told reporters.
A surrender or withdrawal of the rebels from Aleppo would mean the end of the rebellion in the city, delivering Russian-backed President Bashar al-Assad his biggest battlefield victory in the civil war.
Churkin said: "Now it's going to be under the control of the Syrian government, so there is no need for the remaining civilians to leave and there are humanitarian arrangements in place."
The diplomat said Russian military personnel had not seen "any abuses of international humanitarian law."
Russia has vetoed six Security Council resolutions on Syria. China joined Moscow in vetoing five of those resolutions.
"In recent days and hours we appear to be witnessing nothing less than an all-out effort by the Syrian government and its allies to end the country's internal conflict through a total uncompromising military victory," Ban told the Security Council.
Nearly 600 civilians have been killed during the intensified violence in Aleppo during the past month, the Syrian Observatory for Human Rights reports.
In the rebel-held eastern districts, 463 civilians - among them 62 children - were killed as a result of intensive airstrikes and artillery shelling. In the government-run sector, some 130 civilians, including 40 children, were killed by rebel shelling. That's a total of 593 civilians.
At least 532 rebel fighters also died, while 256 soldiers and militia members fighting for the government also died in the conflict. More than 4000 people were reported as injured.
The UN human rights office said it had reports of abuses, including that the army and allied Iraqi militiamen summarily killed at least 82 civilians in captured districts of the city.
"The reports we had are of people being shot in the street trying to flee and shot in their homes," said Rupert Colville, spokesman for the UN office. "There could be many more."
Mr Colville said he feared retribution by government forces.
"In all, as of yesterday evening we have received reports of pro-government forces killing at least 82 civilians, including 11 women and 13 children," Colville told a news briefing, naming the Iraqi armed group Harakat al-Nujaba as reportedly involved in the killings.
Abu Malek al-Shamali, a resident in the rebel area, said dead bodies lay in the streets. "There are many corpses in Fardous and Bustan al Qasr with no one to bury them," he said.
State television broadcast footage of a tide of hundreds of refugees walking along a ravaged street, wearing thick clothes against the rain and cold and hauling sacks or bags of belongings.
France has called for an immediate UN Security Council resolution to discuss alleged atrocities being carried out in eastern Aleppo, Foreign Minister Jean-Marc Ayrault says.
"In the face of allegations of exactions in Aleppo, France calls for a UN Security Council meeting," Ayrault said on his Twitter account on Tuesday.
He earlier told LCI television that the meeting, which should take place as soon as possible, should discuss the possible war crimes and crimes against humanity that were being carried out and that a UN investigation should begin immediately to determine the culprits.
Meanwhile, Qatar has called for an emergency Arab League meeting to discuss the situation in Aleppo, Al Jazeera television reports.
Qatar is a main supporter of rebels who have been fighting to overthrow Syrian President Bashar al-Assad, who is backed by Russia and Iran.
The Qatar-based satellite channel said the request was made for a meeting at the level of representatives to the Cairo-based Arab League, but gave no further information.
Reuters / DPA