MOSCOW: Russia's military on Thursday said it had completely demined the UNESCO world heritage site of Palmyra in Syria after it was recaptured by government forces from the militant Islamic State (IS) group fighters last month.

“As of today the tasks to demine the ancient architectural part of Palmyra have been completed in their entirety,” Yury Stavitsky, the commander of Russia's military engineers, told President Vladimir Putin in a televised video link-up from Syria.

Stavitsky said that Russian sappers had discovered and defused 2,991 explosive devices at the 234-hectare (580 acre) site and along 23 kilometres of road leading to it.

“Now the units of engineers have moved on to demining the residential area of the town of Palmyra and the airport, “ Stavitsky reported.

“367 buildings have been checked, 40 hectares of territory and 9.5 kilometres of roads. 1,432 explosive devices have been destroyed."

Some 560 hectares in the modern town remain to be demined, he added.

“Pass on my gratitude to all the personnel: officers, rank-and-file, those providing security. Thank you very much. I wish you success,” President Putin said in the broadcast.

Palmyra was retaken from IS by government forces -- backed up by Russian firepower -- on March 27.

The militants had blown up UNESCO-listed temples and looted ancient relics at the site -- known as the “Pearl of the Desert” -- after overrunning it in May 2015.

The recapture of Palmyra and its world famous antiquities has been one of the biggest victories for Moscow since it launched a bombing campaign to support President Assad in September, a move that sparked condemnation in the West.

The demining mission was personally ordered by President Putin.