By Michelle Nichols
UNITED NATIONS (Reuters) - The United Nations Security Council will vote on Thursday on a U.S. bid to renew an international inquiry into who is to blame for chemical weapons attacks in Syria, diplomats said, a move that could trigger Russia's 10th veto to block action on Syria.
The mandate for the joint inquiry by the U.N. and the Organization for the Prohibition of Chemical Weapons (OPCW), which found the Syrian government used the banned nerve agent sarin in an April 4 attack, expires at midnight Thursday.
While Russia agreed to the 2015 creation of the inquiry, known as the Joint Investigative Mechanism (JIM), it has consistently questioned its findings, which also concluded that the Syrian government used chlorine as a weapon several times.
Moscow vetoed an initial U.S. bid on Oct. 24 to renew the inquiry, saying it wanted to wait for the release two days later of the latest JIM report that blamed a sarin gas attack on the Syrian government. Russia has since proposed a rival draft resolution to renew the JIM and correct its "systemic errors."
A spokesman for the U.S. mission to the United Nations said on Monday that Russia has refused to engage in negotiations on the U.S. draft resolution. Diplomats said the United States had amended its draft in a bid to win Russian support.
It was not immediately clear how Russia would vote on the U.S. draft and if Moscow would put its own draft text to a vote. Diplomats said the Russian draft resolution had little support among the 15-member council.
British U.N. Ambassador Matthew Rycroft warned on Wednesday that if the inquiry ended: "The only victors would be people who want to use chemical weapons in Syria, which is the (Syrian President Bashar) al-Assad regime plus Daesh (Islamic State)."
"Everyone in the Security Council would be shooting ourselves in the foot if we allowed that to happen," he said.
The Russian mission to the United Nations was not immediately available for comment on the impending council vote.
If the inquiry is not renewed, Russian U.N. Ambassador Vassily Nebenzia said on Monday: "It may send a bad signal, but the way the investigation has been conducted sends an even worse signal."
A resolution needs nine votes in favor and no vetoes by the United States, France, Russia, Britain or China to be adopted. Russia has vetoed nine resolutions on Syria since the conflict started in 2011, backed by China on six occasions.
Syria agreed to destroy its chemical weapons in 2013 under a deal brokered by Russia and the United States.
(Reporting by Michelle Nichols; Editing by James Dalgleish)