MOSCOW (Reuters) - Russian Foreign Minister Sergei Lavrov said on Saturday (Dec 3) Moscow was ready for talks with the United States about a complete withdrawal of all rebels from Syria's eastern Aleppo.

Syrian government forces have captured 60 per cent of the area previously held by rebels in eastern Aleppo after gaining new ground on the city's eastern edge, the Syrian Observatory for Human Rights said on Saturday.

At least seven plumes of smoke were seen rising from rebel-held areas of the city on Saturday morning as the sound of jets could be heard overhead, a Reuters witness in the government-held western Aleppo said.

The Syrian army backed by allied militia has captured large areas of rebel-held eastern Aleppo in the last week in a ferocious campaign that threatens to deal a major defeat to the rebellion against President Bashar al-Assad.

The Observatory and a Syrian military source said the army had built on its gains by capturing the Tariq al-Bab district late on Friday.

A Turkey-based official with one of the rebel groups in Aleppo said government forces had advanced in the area but rebels were repelling them.

Observatory Director Rami Abdulrahman said the total area lost by the rebels was "easily 60 per cent".

The Observatory said at least three people were killed in an air strike on the al-Shaer neighbourhood of eastern Aleppo.

The civil defence rescue service in eastern Aleppo said a gathering of displaced people had been struck and put the death toll at more than six. The army denies targeting civilians.