At least 13 people died in the attacks that were carried out from April to August, according to the report by the Hague-based OPCW

The United States has called on the United Nations Security Council to take tough action against Syria – including possible military action – for its use of chemical weapons – especially chlorine gas.

A U.S. draft resolution – obtained by Al Arabiya News – also demands that Syria cooperate with the Organization for the Prohibition of Chemical Weapons (OPCW) fact-finding mission.

The document calls on the United Nations to condemn “in the strongest terms any use of any toxic chemical, such as chlorine, as a weapon” in Syria.

In February the OPCW Executive Council expressed “serious concern… with a high degree of confidence that chlorine has been used repeatedly and systematically as a weapon in the Syrian Arab Republic.”

Now the draft document reaffirms “that the use of chemical weapons constitutes a serious violation of international law” and calls for those responsible for using them to be held accountable.

Under the existing U.N. Security Council resolution 2118 Syria is banned from holding or using, and developing chemical weapons, as well as stockpiling them or transporting or supplying them to other states.

This latest move follows a report by the OPCW chemical watchdog in January that concluded “with a high degree of confidence” that chlorine gas had been used in attacks on three villages in Syria last year.

At least 13 people died in the attacks that were carried out from April to August, according to the report by the Hague-based OPCW.

While the report did not attribute responsibility for the chlorine attacks, it cited 32 witnesses who saw or heard the sound of helicopters as bombs struck and that 29 smelled chlorine. Only the Syrian regime has helicopters.

President Bashar al-Assad’s regime and the rebels have accused each other of using chemical agents, including chlorine, in the nearly four-year war that has killed more than 210,000 people.

Gas ‘used against ISIS’

In December last year the Syrian Observatory for Human Rights said the Syrian regime had used chlorine gas against Islamic State of Iraq and Syria (ISIS) fighters to halt them from advancing towards its key air base in the eastern city of Deir Ezzor.

At the time the Observatory reported that it received “confirmed reports of suffocation cases in ISIS that the regime forces used the chlorine gas during the bombardment.”

“ISIS pulled back from areas in the mount of Deir Ezzor after it was exposed to regime’s heavy bombardment,” the London-based monitor said.

The Assad regime agreed to hand over its chemical arsenal after a sarin gas attack in August 2013 outside Damascus that left many hundreds of men, women and children dead.

But it did not have to declare its stockpile of chlorine as part of a disarmament deal agreed in 2013, because it is widely used for commercial and domestic purposes- despite being a toxic agent that can be considered a chemical weapon.

The draft document is could come up for a vote on Friday. But it is unclear whether Assad’s ally – Russia – will support the text.

And even if this document is passed, Russia could still prevent further action against Damascus being approved by the council.

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