Moscow, Mar 19 (IANS): Russian authorities said its warplanes carried out up to 25 air strikes around the Syrian city of Palmyra targeting the Islamic State (IS) who captured the ancient city last May, the media reported on Saturday.

The strikes come after the Russian defence ministry on Tuesday announced that its airbase in Syria was preparing aircraft to return home following a surprise withdrawal order by President Vladimir Putin on Monday, BBC reported.

However, US officials said Russia staged no air strikes in Syria in the past week.

US Central Command spokesman Patrick Ryder said there were some bombardments in the Palmyra region but that they were thought to be made by Russian artillery.

Russia had withdrawn most if not all of its strike aircraft and there had been little movement of its ground forces, Ryder said.

Meanwhile, IS claimed on Friday that it had killed five Russian soldiers in fighting around Palmyra in recent days.

Russia has not commented on the claim and there is no independent verification.