BEIRUT (REUTERS) - Syrian government forces and their allies pushed forward against Islamic State fighters to reach the outskirts of the historic city of Palmyra on Wednesday, state media and a monitoring group said.

Clashes raged around Palmyra after government forces took control of most of a nearby hill with air cover from Syrian and Russian warplanes, the Britain-based Syrian Observatory for Human Rights said.

State news agency SANA quoted a military source who said the army and allied militia advanced in the hills outside Palmyra and towards a road junction "after eliminating the last terrorist Daesh groups there", referring to Islamic State fighters.

The Syrian army is trying to recapture Palmyra, which Islamic State seized in May, to open a road to the mostly IS-held eastern province of Deir al-Zor.

Russian President Vladimir Putin, who said last week he was withdrawing most Russian forces after a five-month military intervention which turned the tide of Syria's war in favour of President Bashar al-Assad, has predicted the Syrian army will retake Palmyra soon.