Syrian government forces have recaptured several areas near Aleppo's Old City from rebels, state media and the British-based Syrian Observatory for Human Rights says.
The neighbourhoods included al-Shaar, which a rebel official said on Monday was on the verge of falling.
The areas captured on Tuesday were mostly to the east and northeast of the Old City, but the army and its allies were also pressing forward to its southeast, state television and the Observatory reported.
If government forces close the less than one-mile gap between the Old City's citadel and a neighbourhood to the east, it will seal off another pocket of rebel control and significantly reduce opposition-held territory that has shrunk rapidly in recent weeks.
The recapture of Aleppo, long divided between government and opposition control in the country's nearly six-year civil war, is a strategic prize sought by President Bashar al-Assad, who is backed by Russia, Iran and Shi'ite fighters from Iraq, Lebanon and elsewhere.
It was Syria's second-largest city before the war.
Tens of thousands of civilians are believed to remain trapped in eastern, rebel-held areas which are being bombarded by government forces.
Source: AFP