The world's chemical arms watchdog took the unprecedented step of condemning Syria and the Islamic State group on November 11 for using toxic weapons.
The executive body of the Organization for the Prohibition of Chemical Weapons also voiced concern about "gaps and discrepancies" in Syria's 2013 declaration about the size of its toxic arms stockpile.
In a resolution adopted by a rare majority vote, it said it "condemns in the strongest possible terms the use of chemical weapons in the Syrian Arab Republic."
It pointed to findings by a recent joint investigation with the United Nations which concluded that Syria and IS had used chemical weapons in four documented incidents in 2014 and 2015.
The group urged Syria. which has denied using chemical weapons, "to comply fully with its obligations" under the chemical weapons ban treaty, which Damascus signed in 2013.
The group said the regime's chemical warfare must "desist immediately" and it demanded that Damascus authorize additional inspections of sites in Syria where further alleged incidents have been reported.
The group's mandate to investigate instances of chemical use in Syria expires next week, and diplomats said Russia likely will block an extension.