Damascus, Jan 23 (IANS): The bombing of the historic heritage in the ancient oasis city of Palmyra by the Islamic State (IS) militant group is a "war crime", the Syrian Culture Minister has said.

The recent bombing of the facade of the historic amphitheatre as well as other relics and monuments in Palmyra targeted Syrian heritage and culture, Xinhua news agency quoted Muhammad Ahmad as saying on Sunday.

"These monuments are not only the property of Syria, but the whole world," Ahmad said, urging the international community to shoulder its responsibility in protecting the world heritage.

"Any inaction in this difficult time threatens Palmyra and will be a clear runaway from the humanitarian and ethical duty in protecting and preserving the world heritage," he said.

The IS last Friday destroyed the facade of the ancient Roman theatre and the Tetrapylon in Palmyra.

The interface of the theatre was completely demolished after being booby-trapped, so was the famous Tetrapylon, an ancient Roman monument of a cubic shape, in that millennia-old city.

One month ago, the group stormed the city for the second time after losing it to the Syrian Army nine months earlier.

In its first invasion of Palmyra in 2015, the IS destroyed key temples and monuments.

Ahmad said the presence of the IS in Palmyra exposed the city to further destruction and would push it into a "scary nightmare".

Regarding the ancient part of the city of Aleppo, which was under the rebels' control for four years before the army wrested back control of that area late last year, Ahmad said 40 per cent of old Aleppo was still in a good condition, 30 per cent in a medium condition and the rest in a "catastrophic status".