The opposition Syrian National Council issued a cry for help yesterday to save Homs and other cities from attacks by President Bashar al-Assad’s regime, repeating its call for UN intervention.

“The country is under a violent attack, especially Homs,” said Abdel Basset Sayda, the leader of the SNC, Syria’s main opposition group.

“This criminal regime is still trying to commit atrocities” in Homs and elsewhere, including the central town of Rastan and the northern city of Aleppo, he told journalists.

The Syrian army tightened its grip yesterday on Homs, assaulting the besieged central city with shelling and gunfire.

SNC’s Bassma Kodmani said the situation there was growing increasingly desperate. “The city is left with no food, no electricity, no water, no communications,” she said.

Other towns, including Rastan, “are living through tragic hours and days”, she said.

“We are calling for immediate humanitarian intervention in favour of the people of Syria.”

Mr Sayda and Ms Kodmani both repeated the SNC’s call for the United Nations to pressure Assad’s regime using Chapter VII of the UN charter, which allows measures to be imposed on a country under penalty of sanctions or force.