Syrian government forces have seized a key district in eastern Aleppo as rebels lost further ground in recent days.

Troops loyal to Bashar al-Assad re-took the strategic eastern district of al-Sakhour in a wider advance that has driven rebels from a third of their territory in the besieged city, according to the Syrian Observatory for Human Rights.

It has also been reported that the rebels have lost control of the northern section of opposition-held eastern Aleppo.

Rami Abdulrahman, Director of the Observatory, said: "It is the biggest defeat for the opposition in Aleppo since 2012.

"The opposition has lost more than third of the area it controlled in Aleppo city during the big advance".