Syrian president Bashar el-Assad has responded for the first time to claims that he was responsible for the chemical attack in Idlib last week which killed 150 and wounded hundreds. Assad claimed that the attack was a 'fabrication' and said that the Syrian army had already relinquished its chemical weapons reservoir.

The report came a short time after the Syrian army claimed that the US had attacked an ISIS chemical weapons depot Wednesday, "killing hundreds including civilians". The US has denied these reports.

Meanwhile, samples taken from the chemical weapons attack in Idlib tested positive for the nerve agent sarin, the British delegation at the world's chemical weapons watchdog said.

"UK scientists have analysed samples taken from Khan Sheikhoun. These have tested positive for the nerve agent sarin,or a sarin-like substance," the delegation said during a special session at the Organisation for the Prohibition of Chemical Weapons in The Hague.