Syria, Russia under pressure at chemical weapons watchdog
Moscow was urged by Western nations to "transparently" reveal the circumstances of the Novichok nerve agent poisoning of opposition figure Alexei Navalny.
"The Syrian Arab Republic has not completed any of the measures," Arias told the meeting.
He said "gaps, inconsistencies and discrepancies" remained in Syria's account of its progress on its 2013 agreement to give up all chemical weapons following a suspected sarin attack that killed 1,400 people in the Damascus suburb of Ghouta.
France proposed that the OPCW should "suspend the rights and privileges" of Syria for failing to meet the deadline, French ambassador Luis Vassy said, adding that the proposal was backed by 43 states.
These would include Syria's voting rights in the OPCW, depriving it of a voice at a body where it has been deflecting allegations of toxic arms use for years.
The OPCW has confirmed traces of the Soviet-era nerve agent Novichok in samples taken from Navalny in hospital in Germany, where he is recovering.
Arias said the OPCW was still in talks with Russia to send a fact-finding team there to investigate the incident, he said.
In a joint statement, 55 countries including the United States, Japan, Canada, Australia and many in Europe said they "condemn in the strongest possible terms" the attack on Navalny.