Syrian government forces have retaken all of Palmyra in a major victory over the so-called "Islamic State" jihadi group, AFP said.

“After heavy fighting during the night, the army is in full control of Palmyra – both the ancient site and the residential neighbourhoods,” a military source told AFP.

ISIS fighters pulled out on Sunday morning, retreating to the towns of Sukhnah, Raqqa and Deir ez-Zor to the east.

“Army sappers are in the process of defusing dozens of bombs and mines planted inside the ancient site,” the source added.

The British-based Syrian Observatory for Human Rights (SOHR) said there was still gunfire in the eastern part of the city on Sunday morning but the bulk of the Islamic State force had pulled out and retreated east, leaving Palmyra under government control.

The announcement came after Syrian troops backed by Russian ground and air forces on Saturday pushed deeper into the Isis stronghold.

(With inputs from AFP)