The Syrian army has halted its attacks on Syria's Aleppo to allow for the evacuation of civilians, according to Russian Foreign Minister Sergei Lavrov.

"I can tell you that today, combat operations by the Syrian army have been halted in eastern Aleppo because there is a large operation underway to evacuate civilians," he said in Hamburg, Germany, cited by Russian news agencies.

"There is going to be to a column of 8,000 evacuees" travelling 5km, added the Russian minister, attending a meeting of the Organization for Security and Cooperation in Europe (OSCE).

In Washington, White House spokesman Josh Earnest said the announcement was "an indication that something positive could happen".

Mr Lavrov meanwhile announced that US-Russia military and diplomatic discussions would take place in Geneva on Saturday "to end the work ... to define the means of resolving the problems of east Aleppo".

The discussions would notably study plans to evacuate rebel fighters and civilians who want to leave, according to the Russian minister.

Mr Lavrov and his US counterpart John Kerry briefly talked today in the sidelines of the OSCE meeting, but a US official said there was no progress or conclusions on Aleppo.

The two men had seen each other the previous evening in Hamburg, but were unable to make any progress on a plan for a cessation of fighting and evacuation of rebels and civilians in Aleppo.

Rebel fighters are on the verge of losing control of their last strongholds in the face of Syrian troops backed by Russia and Iran.

Mr Lavrov's announcement came after six western countries including the United States called for an immediate ceasefire in the face of the humanitarian catastrophe in Aleppo, urging Russia and Iran to use their influence on the Syrian regime to secure a truce.

Civilians evacuated from Aleppo hospital

Nearly 150 civilians, most with disabilities or in need of medical care, were evacuated from a hospital in Aleppo's Old City overnight.

It marked the first major evacuation from the city’s eastern sector, the International Committee of the Red Cross has said.

"These patients and civilians had been trapped in the area for days because of heavy clashes nearby and as the front line kept drawing closer," said the head of the ICRC delegation in Syria, Marianne Gasser, who is in the city.

Among those evacuated from Dar Al-Safaa hospital in the Old City - reclaimed by Syrian government forces on Tuesday – 118 patients were taken to three hospitals in the west of Aleppo and 30 people were taken to shelters, also in the west of the city, the ICRC said in a statement.

The evacuation was conducted jointly with the Syrian Arab Red Crescent, it said.