France and Turkey have said that air strikes on hospitals in northern Syria constitute war crimes. Up to 50 people have been killed in missile attacks on schools and hospitals in the region, the UN said. Turkey's foreign ministry blamed Russia for the attacks. Moscow is yet to respond to the allegations. Meanwhile, Syrian President Bashar al-Assad has cast doubt over plans to implement a "cessation of hostilities" in Syria. Last week world powers agreed to work towards a selective truce in Syria, to begin later this week.

But in his first comments on the announcement, President Assad said such a ceasefire did not mean all the parties would put down their weapons. "So far they say they want a ceasefire within a week," he said in televised comments. "Who is capable of gathering all these conditions and requirements within a week?" The UN said the series of raids in northern Syria "cast a shadow" on the prospects for a cessation.

At least 12 people were killed in Azaz and the surrounding area, with two hospitals and two schools reportedly hit. In Maarat al-Numan, in Idlib province, a hospital run by Medecins Sans Frontieres (MSF ) was reduced to rubble. Seven people were killed and another eight are still missing the medical charity said, calling it a "deliberate" attack.