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MOSCOW, May 20 (Reuters) - Russia will veto a draft U.N. resolution to refer the civil war in Syria to the International Criminal Court if it comes to a vote in the Security Council, Interfax news agency quoted a Russian official as saying on Tuesday.
France circulated a draft resolution to U.N. Security Council members on May 12 that seeks to refer the three-year-old conflict to the ICC for possible prosecution of war crimes and crimes against humanity.
Russia had already voiced opposition to a referral, but Deputy Foreign Minister Gennady Gatilov's remarks were the clearest warning yet of a veto.
"The draft that has been submitted to the U.N. Security Council is unacceptable to us, and we will not support it," Gatilov was quoted as saying. "If it is put to a vote, we will veto it."
Russia has been President Bashar al-Assad's most powerful diplomatic backer during the war, blocking - along with China - three resolutions that would have condemned his government, threatened sanctions and called for war crimes accountability.
Russia and the United States initiated a peace process that led to talks between the government and its opponents, but it has faltered and Moscow's confrontation with the West over Ukraine has further reduced the chances for success.
(Writing by Steve Gutterman, Editing by Timothy Heritage)