Syria said its military command was still studying a proposal for a holiday ceasefire with rebels – contradicting international mediator Lakhdar Brahimi's earlier announcement that Damascus had agreed to a truce.

Yesterday's statement threw Mr Brahimi's efforts to arrange a pause in the bloodshed in Syria into even more confusion, as rebels fighting to topple President Bashar al Assad have given no indication they would be willing to sign up to it.

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

Mr Brahimi, the joint UN-Arab League special envoy, had crisscrossed the Middle East to push the warring factions and their international backers to agree to a truce over the Muslim holiday of Eid al Adha – a mission that included talks with Mr Assad in Damascus at the weekend.

"After the visit I made to Damascus, there is agreement from the Syrian government for a ceasefire during the Eid," Mr Brahimi told a news conference at the Arab League in Cairo.

However, within an hour, Syria's Foreign Ministry said the proposal was still being studied by the armed forces' leadership. "The final position on this issue will be announced tomorrow," a ministry statement said.

The holiday starts tomorrow and lasts three or four days.

Mr Brahimi did not specify how long the truce would last. Nor did the initiative include plans for international observers.

Rebel sources had said there was little point of a truce if it could not be monitored or enforced.

The two sides in Syria are now locked in a battle with huge potential ramifications in the north-west.

Syrian warplanes carried out bombing raids yesterday on the strategic northern town of Maarat al Numan and nearby villages, while rebels surrounded an army base to its east, an activist monitor said.

Five people from one family, including a child and a woman, were killed in the air strikes, according to Rami Abdelrahman, head of the British-based Syrian Observatory for Human Rights.

Maarat al Numan has fallen to the rebels, effectively cutting the main north-south highway, a strategic route for the Assad regime to move troops from Damascus to Aleppo, Syria's largest city where the insurgents have taken a foothold.

But without control of the nearby Wadi al Daif military base, their grip over the road is tenuous. Its capture would be a significant step towards creating a safe zone allowing them to focus forces on Assad strongholds in southern Syria.

The rebels say the ferocity of counter-attacks by government forces shows how important holding the base is to the Assad military strategy.

Opposition footage yesterday showed a column of grey smoke rising after a bomb hit the village of Deir al Sharqi, a few miles south of the base.

Activists and Syrian state media also traded blame for the killing of at least 25 people, including women and children, in the town of Douma, near Damascus.

"More than 20 civilians have been slaughtered by [pro-government militia[ shabiha who were at a checkpoint and then stormed into a residential building nearby," opposition media said.

Syrian state television said 25 people had been killed by "terrorists".