U.S. President Barack Obama, right, listens to Russia’s President Vladimir Putin before the opening of the first plenary session of the G-20 Summit in Los Cabos, Mexico, Monday, June 18, 2012.

Diplomats said on Thursday the United States has refused to negotiate over a draft statement that Russia had hoped the U.N. Security Council would approve to bolster its position on Syria ahead of a major gathering of world leaders.

A draft of Russia’s council statement, obtained by The Associated Press, urges countries to fight extremist groups “in coordination with the governments of the affected states.”

That language can be seen as a reference to Syria’s government, which Russia supports. Russian military shipments to Syria have alarmed the U.S. and its allies in recent weeks, and President Vladimir Putin is expected to defend them in a U.N. speech Monday.

A Kremlin spokesman has said Putin will meet President Barack Obama on Monday.

Sheba Crocker, the assistant U.S. secretary of state for international organization affairs, confirmed that the U.S. told Russia it couldn’t support its proposed statement on Syria.

“We have concerns that a council presidential statement could be perceived as endorsing an approach that could set back efforts to reach a negotiated political transition in Syria,” Crocker told reporters in Washington. She said the draft was at “significant variance with the ongoing efforts of a coalition of more than 60 countries, including all of Syria’s neighbors to counter ISIL.”

Russia’s proposal is for a presidential statement, a political statement that shows important council backing. Last month, the Security Council found rare unity on Syria to unanimously approve such a statement supporting the U.N. envoy on Syria’s new plan aimed at setting the stage for new peace talks.

That came during a flurry of diplomatic activity to try to end Syria’s conflict, now in its fifth year.

One Security Council diplomat, speaking on condition of anonymity because the discussion was not a public one, said Russia’s new military buildup put a damper on those diplomatic efforts.

Russia’s draft seeks to draw the global community into a united effort to fight extremism. It also urges countries in the Middle East “to combat terrorism as a primary regional security concern and coordinate their actions” against the Islamic State of Iraq and Syria (ISIS) group, al-Qaeda and other organizations.

But the U.S. and its allies object strongly to any coordination with Syrian President Bashar Assad. About 4 million people have fled Syria during the conflict, which the U.N. says has killed more than 250,000.