Member states of the global chemical weapons watchdog voted Wednesday to strip Syria of its rights at the organisation in an unprecedented step after a probe blamed Damascus for poison gas attacks.

A motion backed by countries including France, Britain and the United States to suspend Syria's "rights and privileges" obtained the required two-thirds majority in the vote at the Organisation for the Prohibition of Chemical Weapons (OPCW).

"In light of this result the draft resolution is adopted," said Jose Antonio Zabalgoitia Trejo, the chairman of the meeting of the OPCW's member states who had gathered at its headquarters in The Hague.

Eighty-seven countries voted in favour of the motion, 15 including Syria, Russia, China and Iran voted against, and 34 abstained, OPCW officials said. A total of 136 out of the agency's 193 member states voted.

The measures are in response to an OPCW investigation last year that found the Syrian air force had used the nerve agent sarin and chlorine gas in three attacks on the village of Latamenah in 2017.

The motion said the OPCW "decides, after careful review, and without prejudice to the Syrian Arab Republic's obligations under the (Chemical Weapons) Convention, to suspend the following rights and privileges."

These include the right to vote in either the annual conference of all member states or the OPCW's executive council, to stand for election in the executive council, or to hold any office in the agency, it said.