Thousands of civilians spent the night in bombed out apartment blocks in rebel Aleppo in desperate hope of a resumption of organised evacuations on Saturday, an AFP correspondent reported.

Entire families camped out in whatever shelter they could find in the rebel-held part of Al-Amiriyah district, which was the departure point for evacuations before they were suspended by the Syrian government on Friday.

Temperatures plummeted to minus 6 Celsius (52 Fahrenheit) overnight, an appalling challenge for the remaining civilians in rebel areas who have received no aid deliveries since June.

Many had not had a proper meal in days and were surviving on just a few dates, AFP's correspondent reported.

Anticipating evacuation, a lot of people had burned all possessions they could not carry with them, determined not to allow them to be looted by victorious government troops and militia.

The precise number of people still trapped in the last rebel-held pocket southwest of the city centre 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 rebel fighters but the world body has since acknowledged there is uncertainty about the figures.

Before evacuations were suspended on Friday, 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 Russian defence ministry said after the suspension 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, not just from rebel Aleppo, but also from other besieged areas.

Turkish Foreign Minister Mevlut Cavusoglu, whose government is a key backer of the opposition, said he had spoken ‘13 times’ with his Iranian counterpart, Mohammad Javad Zarif, during the day.

Iran and Russia are the main allies of the Syrian government.

Tehran has reportedly joined Damascus in insisting on evacuations from two mainly Shia villages in the northwest under siege by the rebels in exchange for renewed departures from Aleppo.

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