The United Nations said on Tuesday it had reports of Syrian government troops and allied Iraqi militia killing civilians in eastern Aleppo, including 82 people in four different neighbourhoods in the last few days.
Rupert Colville, spokesman of the U.N. human rights office, voiced deep fear of retribution against thousands of civilians still believed to be holed up in a "hellish corner" of less than a square kilometre of opposition-held areas.
Aid groups in Syria, including the International Committee for the Red Cross and the White Helmets, have appealed for safe passage for civilians caught in the fighting as regime forces close in on pockets of rebel resistance in the city.
Turkey on Tuesday said it was continuing efforts with the United States, Iran, the European Union, and the Gulf States to evacuate Aleppo. Turkish Foreign Minister Mevlut Cavusoglu said a ceasefire was needed for the evacuation. A senior Turkish official said a regularly scheduled meeting between Russian and Turkish officials on Wednesday would discuss the possibility of a ceasefire and opening a corridor to evacuate rebels and civilians.
Syrian regime leader Bashar al Assad's forces now hold more than 90 percent of the one-time opposition stronghold of east Aleppo, and appear on the verge of retaking the entire city. Assad's forces and allied militias on Tuesday took control of all the Aleppo districts abandoned by rebels during their retreat from the city, a regime source said.
The fall of Aleppo would deal the rebels their worst defeat since the beginning of the Syrian conflict in 2011, and leave the regime in control of the country's five major cities.
TRT World 's Ediz Tiyansan has more.