°®Âþµº

At least seven civilians, including five children, were killed by airstrikes in Syria's northwestern Idlib province on Tuesday, the last city outside government control, a monitor said.

The airstrikes targeted the town of Khan Subul in the centre of Idlib province, the UK-based Syrian Observatory for Human Rights said.

"There were at least seven dead, five children and two women," the Observatory said. 

"We do not know if these were airstrikes by the Syrian regime or the Russians," Observatory head Rami Abdel Rahman told AFP.

Regime and allied forces backed by Russian warplanes have been battling Syria's rebels for more than a week in an area straddling the boundary between Idlib and Hama provinces.

The official SANA news agency said the army took control of six villages in the central Hama province.

Damascus' push on the edge of Idlib province follows two months of sporadic fighting that the UN has displaced more than 60,000 people.

"Displacement sites are reportedly overwhelmed. Some services are 400 percent above their planned capacity to serve," the United Nations Office for the Coordination of Humanitarian Affairs said. 

An AFP correspondent said there were more clashes on Tuesday.

A column of white smoke could be seen after a regime airstrike on the town of al-Tamana, and rebel artillery was targeting government positions.

A commander of the Hayat Tahrir al-Sham - an alliance of rebel forces dominated by a former al-Qaeda affiliate - said Syrian troops were trying to reach a military airport.

"The regime's goal is to reach Abu al-Duhur airport. All the talk about their aim to reach Idlib province is completely false," said the commander going by the name of Abu Islam.

He said rebels and jihadi groups have buried their "differences" and set up a joint command to battle regime forces.

Idlib province, mostly held by Tahrir al-Sham, was one of four "de-escalation zones" agreed to help halt fighting around Syria by regime backers Russia and Iran and rebel supporter Turkey.

The war in Syria has killed more than 340,000 people and displaced millions from their homes since it began in 2011 with the brutal repression of anti-government protests.