Russia says it will extend a pause in airstrikes on Aleppo until the evening of November 4, two days from now.
The announcement from the country’s defence ministry said the move was by order of President Vladimir Putin.
On Tuesday the Kremlin said a temporary pause in Russian and Syrian airstrikes was still in force, but could not be extended if rebels in the city did not halt their attacks.
Video released by the Syrian army shows government troops engaged in heavy fighting with rebel forces in the west of the city.
Tanks and heavy artillery are used as opposition fighters come under fire.
Rebel groups have launched an assault on western districts in recent days to try to lift a siege on the eastern half of the city, where it’s thought over a quarter of a million people are surrounded by forces loyal to the government.
The United Nations has said all sides fighting over Aleppo may be committing war crimes through indiscriminate attacks in civilian areas. It says attacks by rebel groups in western districts may have killed dozens of people.
Pledging to serve his full term in office until 2021, President al-Assad has attacked the media in the West for branding terrorists as freedom fighters and painting a black and white picture of the war.
The bombardment of civilian areas by his and Russian forces has been condemned as barbaric, with the UN describing Aleppo as a “slaughterhouse”.