At least 14 civilians have been killed in an air raid by the Syrian government and Russian forces on the rebel-held Idlib province.

Seven of Wednesday's victims were killed in the village of Sarja, four others - a man and his three children - in the village of Bara and three more in Hbeit town, according to the activist-operated Baladi news agency and the Britain-based Syrian Observatory for Human Rights (SOHR).

The White Helmets civil defence volunteers put the death toll at 15.

“The bombardment by the regime and Russia continues to be intense on several areas,” said SOHR chief Rami Abdelrahman.

The northwestern Syrian province of Idlib, a rebel enclave where most of it is controlled by the Hayat Tahrir al-Sham armed group, is home to almost three million people.

Syrian state news agency SANA reported one woman was killed by rebel shelling on northern Hama.

Government strategy

The regime has not announced an all-out offensive to retake the entire enclave.

Analysts predict that the government of President Bashar al-Assad and its allies will continue to chip away at the area, but not unleash a major assault that would create chaos on Turkey's doorstep.

The regime is likely to continue applying sustained military pressure whilst attempting to preserve a fragile truce agreement reached in Russia last year to spare the region a large-scale humanitarian disaster.

On Tuesday, Syria's United Nations (UN) envoy Bashar al-Jaafari said Damascus "will spare no effort" to free the residents of Idlib from rebel control, according to comments carried by SANA.

UN deputy aid chief Ursula Mueller, however, told the UN Security Council that a further escalation would threaten humanitarian assistance for the residents.

She said about 270,000 people had been displaced by the fighting in Idlib since late April.

Aid agencies have been forced to suspend their work in some areas, she said, adding that 22 hospitals and clinics had been hit by air strikes or shelling since April 28.

The United States has said that “indiscriminate attacks on civilians and public infrastructure such as schools, markets and hospitals is a reckless escalation.”

The civilian death toll has mounted in and around Idlib in recent days, reaching more than 270 over the past month, according to SOHR.

In villages targeted by regime raids, excavators dug new graves and civilians buried the dead stealthily at dusk to avoid being targeted by more air raids.

The conflict in Syria has killed more than 370,000 people since it started in 2011. (Aljazeera)

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