Russian fighter jets and Syrian barrel bombs pound Idlib province

Russian and Syrian warplanes have pounded towns in Syria's opposition-held Idlib province, a day after a summit of the presidents of Turkey, Iran and Russia failed to agree on a ceasefire aimed to forestall a Russian-backed government offensive.

Witnesses and rescuers said at least a dozen air strikes hit a string of villages and towns in southern Idlib and the town of Latamneh in northern Hama, where rebels are still in control.

Syrian helicopters dropped barrel bombs, containers filled with explosive material, on civilian homes on the outskirts of the city of Khan Sheikhoun, two residents of the area in southern Idlib said.

Three civilians were killed in the village of Abdeen in southern Idlib, a civil defence source said.

Nearly 60 Russian air raids hit the south and southeast of Idlib province in less than three hours, the Syrian Observatory for Human Rights said.

The Russian strikes as well as the government bombardments with barrel bombs killed at least four civilians, the Observatory added.

Friday's summit had focused on a looming military operation in Idlib, the last major stronghold of active opposition in Syria to the rule of President Bashar al-Assad.

Turkish President Recep Tayyip Erdogan pushed for a ceasefire during the summit, but Russian President Vladimir Putin said a truce would be pointless as it would not involve armed groups on the ground that Assad and his allies deem as terrorists.

Idlib currently hosts about three million people, including one million children, according to the United Nations, and the expected government plans for an assault on the province have raised fears of a humanitarian disaster.

Over half of the civilians have already been displaced at least once from elsewhere in the country and have nowhere left to go

Meanwhile, Syrian Kurdish forces said they clashed with regime fighters in the divided northeastern city of Qamishli on Saturday, leading to the deaths of 18 combatants.

The rare flare-up in the Kurdish-majority city near the Turkish border saw 11 government fighters and seven Kurds killed, the Kurdish security forces said.

The UK-based Syrian Observatory for Human Rights reported the same death toll.