Syria's Foreign Ministry has said military leaders are studying a proposal by international mediator Lakhdar Brahimi for a ceasefire to mark the Islamic holiday of Eid al-Adha.

They said they would announce a decision on Thursday.

Earlier, Mr Brahimi said the Syrian government had agreed to a ceasefire during the holiday. His initiative did not include plans for international observers to monitor a halt to hostilities.

It is not clear whether rebels will commit to a truce.

A previous ceasefire arrangement in April collapsed within days with both sides accusing the other of breaking it.

Meanwhile, activists said Syrian warplanes were carrying out bombing raids on the strategic northern town of Maarat al-Numan and nearby villages while insurgents surrounded an army base to its east.

Hundreds of Syrian refugees have poured into a makeshift refugee camp at Atimah overlooking the Turkish border, fleeing a week of what they said were the most intense army bombardments since the uprising began.

Human Rights Watch said the Syrian air force had increased its use of cluster bombs across the country in the past two weeks.

Russia said rebels had acquired portable surface-to-air missiles, including US-made Stingers - a weapon that would help bring down warplanes and helicopters.