The United Nations Security Council has scheduled a closed-door meeting Tuesday (2000 GMT)) at Russia's request on a resolution aimed at securing and destroying Syria's chemical weapons stockpiles.
Earlier, the Syrian government accepted a proposal from Russia - its most powerful ally - to put its chemical weapons under international control for subsequent dismantling to avoid a possible U.S. military strike.
Meanwhile, British Prime Minister David Cameron said Britain, France and the United States will introduce a U.N. Security Council resolution Tuesday on Syria's chemical weapons.
France said the draft resolution would include the threat of force to ensure compliance, condemn the August 21 chemical weapons attack and call for those behind it to be punished at the International Criminal Court.
"It's on the acceptance of these precise conditions that we will judge the credibility of the intentions expressed yesterday. The Syrian people have suffered too much. We will not fall for delaying maneuvers therefore we need rapid results."
French officials said the resolution was designed to force Syrian President Bashar al-Assad's government to act quickly.
But Russian Foreign Minister Sergei Lavrov told his French counterpart the threat of force was "unacceptable." Russia's Foreign Ministry said Moscow would submit its own proposal allowing for only political and diplomatic settlement to the conflict.
Iran, China and the Arab League have all said they welcomed the Russian plan. But Syria's main opposition bloc, the Syrian National Coalition, dismissed the idea as a largely meaningless measure that would allow Mr. Assad free rein to fight on with conventional weapons.
The Security Council has been unable to agree on previous measures sanctioning Syria, with Russia and China using their veto power to block three previous resolutions against President Bashar al-Assad's government.
In Washington Tuesday, the White House and a bipartisan group of senators began drafting an alternative congressional resolution that would give the U.N. time to take control of the Syrian government's arsenal of the internationally banned weapons.
U.S. President Barack Obama discussed the plan for U.N. talks with French President Francois Hollande and Mr. Cameron before meeting with senators who are wary of U.S. military intervention.
The developments came hours before Mr. Obama plans to deliver a major televised address on the Syrian crisis.