The Assad regime has dismissed as a ''barefaced lie'' US and British claims it might have used chemical arms, with staunch ally Russia warning against using such fears to launch a military intervention.

The developments come with at least 10 people have been killed in shelling on the town of Douma, north-east of the capital Damascus, and renewed fighting in other areas on Saturday.

A firefighter hoses water on a burning gas station, which activists say was the result of shelling by forces loyal to Syria's President Bashar al-Assad in Raqqa province on Friday. Credit:Reuters

''I want to confirm that statements by the US Secretary of State and British government are inconsistent with reality and a barefaced lie,'' Syrian Information Minister Omran al-Zohbi said in an interview with the Kremlin-funded Russia Today TV network.

''I want to stress one more time that Syria would never use [chemical weapons] - not only because of its adherence to the international law and rules of leading war, but because of humanitarian and moral issues.''