Thousands of trapped civilians and rebels waited desperately Saturday for evacuations to resume from the last opposition-held areas of Aleppo after the operation was suspended by the Syrian regime.
A rebel representative told AFP that an agreement had been reached to allow more evacuations from the city, which has been ravaged by some of the worst violence of the nearly six-year war that has killed more than 310,000 people.
But there was no confirmation from President Bashar al-Assad`s regime or its staunch allies Russia and Iran, which are under mounting international pressure to end what US President Barack Obama denounced as the "horror" in Aleppo.
Obama called Friday for impartial observers to monitor efforts to evacuate civilians from the devastated city and warned Assad that he would not be able to "slaughter his way to legitimacy".
Families spent the night in freezing temperatures in bombed out apartment blocks in Al-Amiriyah district, which was the departure point for evacuations before they were halted on Friday, an AFP correspondent reported.
Many had not had a proper meal in days and were surviving on just a few dates.
A lot of people had burned all possessions they could not carry with them, determined not to allow them to be looted by government troops and militia who have recaptured almost the entire city.
The government blamed rebels for the suspension of the evacuation operation which had begun on Thursday, saying they had tried to smuggle out heavy weapons and hostages.
The opposition accused the government of halting the operation in a bid to secure the evacuation of residents from Fuaa and Kafraya, two villages under rebel siege in northwestern Syria.
In return the rebels want the evacuation of the towns of Madaya and Zabadani in Damascus province which are besieged by the regime.
"We are working on a resumption of the operations today (Saturday)," said Al-Farook Abu Bakr, a representative of the hardline Islamist rebel group Ahrar al-Sham.
"There will be evacuations from Fuaa and Kafraya, as well as Madaya and Zabadani, and all the residents of Aleppo and the fighters will leave."
The precise number of people still trapped in the last rebel-held pocket southwest of central Aleppo is unclear.
UN envoy Staffan de Mistura estimated that as of Thursday there were around 40,000 civilians and perhaps as many as 5,000 opposition fighters in the rebel enclave but the world body has since acknowledged there is uncertainty about the figures.
Before evacuations were suspended around 8,500 people, including some 3,000 fighters, left for rebel-held territory elsewhere in the north, according to the Syrian Observatory for Human Rights, a Britain-based monitoring group.
"The evacuations are expected to resume on Saturday in Aleppo, in synchronisation with the evacuation from Fuaa and Kafraya of around 4,000 people -- the wounded and their families, as well as civilians and orphans," Observatory director Rami Abdel Rahman said.
Tens of thousands of civilians had already fled opposition-controlled parts of Aleppo after the regime began its latest assault in mid-November.
The Russian defence ministry said after evacuations were suspended that only hardline rebel fighters remained.
But World Health Organization country representative Elisabeth Hoff said: "There are still high numbers of women and infants -- children under five -- that need to get out."
The main regional supporters of the rival sides in Syria`s devastating civil war engaged in a flurry of diplomacy on Friday to try to secure a resumption of evacuations.
Turkish Foreign Minister Mevlut Cavusoglu, whose government is a key backer of the opposition, said he had spoken more than a dozen times with his Iranian counterpart, Mohammad Javad Zarif, during the day.
On Friday a convoy of evacuees that had already left east Aleppo when the operation was suspended was forced to turn back, an AFP correspondent said.
The International Committee of the Red Cross (ICRC), supervising the evacuations, said it was looking into reports of shooting before the convoy was turned around.
In New York, the Security Council could vote as early as this weekend on a French-drafted proposal to allow international observers in Aleppo and ensure urgent aid deliveries.
Several thousand people protested on the Turkish border on Saturday against the siege of Aleppo, while a demonstration was planned in Berlin.
More than half the Syrian population has been displaced, with millions becoming refugees, since the conflict began with anti-government protests in 2011.
Diplomatic efforts -- including several rounds of peace talks in Geneva -- have failed to make progress in resolving the conflict, which reached a turning point last year when Russia launched an air war in support of Assad.