The surprising move from Russia came as White House officials began their latest round of congressional briefings on possible military action in Syria.
Defense Secretary Chuck Hagel, Chairman of the Joint Chiefs of Staff Gen. Martin Dempsey, Pentagon Comptroller Robert Hale and Director of National Intelligence James Clapper briefed members of the House on a possible Syria operation.
U.S. forces are poised to strike targets in Syria in retaliation for Assad's reported use of chemical weapons against anti-government forces in the country.
Should Assad agree to the plan, the move could be enough to dissuade Washington from carrying out military strikes against the regime's forces.
White House officials are exploring the Russian option, with deputy national security adviser Tony Blinken telling reporters the White House would “welcome a decision by Syria to give up its chemical weapons."
But several senior administration officials, as well as top congressional lawmakers, are highly doubtful that Assad will accept Russia's plan.
White House, Congress question Russia deal: The White House and Congress remain skeptical a Russian-led deal to get Syria to abandon its chemical weapons stockpiles will materialize.
"It's not real at this point," House Armed Services Committee ranking member Rep. Adam Smith (D-Wash.) told reporters on Capitol Hill on Monday.
For his part, committee chief Rep. Buck McKeon (R-Calif.) said Congress and the White House have more work to do with Moscow to see if the plan can become reality.
"We are talking hypotheticals at this point," McKeon said during the same briefing to reporters.
Senate Armed Services Committee chief Sen. Carl Levin (D-Mich.) said Congress and the White House "shouldn’t get our hopes up too high" that Syria will agree.
"If Russia is serious, and not just helping Syria stall, it could make a difference," Levin said in statement Monday.
Congressional doubts over the Russia plan echoed the concerns about the effort expressed by top Obama administration officials.
“Sure. He could turn over every single bit of his chemical weapons to the international community in the next week,” Secretary of State Joh Kerry said on Monday. “Turn it over, all of it, without delay. And allow the full and total accounting for that, but he isn't about to do it.”
The Russia plan comes as the White House is making its final push on Capitol Hill to convince lawmakers to back U.S. military action in Syria.
Obama has maintained the White House has the authority to carry out strikes against Syria without the blessing of Congress. However, the president opted to seek lawmakers' approval, to ensure any action taken has the full support of the American people.
But finding support on Capitol Hill has proven difficult, with members in both parties saying they want to avoid getting the U.S. involved in another conflict in the Middle East.
The White House did clear a major hurdle in gaining lawmakers' support last week, when the Senate Foreign Relations Committee agreed to authorize the use of force in Syria.
Panel members approved military action by a vote of 10 to 7 last Wednesday. Seven Democrats and three Republicans backed the measure, while five Republicans and two Democrats on the committee opposed it.
Obama enlists GOP help to sell Syria: A group of House Republicans who support military strikes in Syria met with White House chief of staff Denis McDonough on Monday to plot out strategy to gain support for military action with the public and lawmakers.
Rep. Pete King (R-N.Y.) told The Hill that the White House meeting with McDonough was held so the administration could solicit ideas to try and turn the tide of mounting “no” votes.
“I think his main thing was this is not going to be a traditional operation to line up votes,” King said, calling the meeting “constructive."
“It was more about asking us for ideas as to what the president can say or what the White House can do to try to win support — both public support and congressional support — to try to move the needle,” he said.
Reps. Mike Rogers (R-Mich.), Mike Pompeo (R-Kan.), Tom Cotton (R-Ark.) and Adam Kinzinger (R-Ill.) also attended the meeting with McDonough, King said.
The five GOP lawmakers are part of a small group of House Republicans who have come out in favor of taking military action, while more than 100 of their GOP colleagues have expressed opposition to strikes.
Speaker John Boehner (R-Ohio) and Majority Leader Eric Cantor (R-Va.) have both publicly backed military action in Syria, but they said they are not planning to whip votes in their conference.
The meeting with Republican lawmakers Monday is part of a major push by the White House to convince the public and lawmakers that limited military action in Syria is the right course of action.
NATO says strikes are only option in Syria: Military action is the only way to guarantee embattled Syrian President Bashar Assad does not launch a new round of chemical weapon strikes in the future, according to the head of NATO.
"Personally it is my firm view that it should be a military response. The aim of that should be to ensure that such attacks with chemical weapons will not happen again," Secretary General Anders Fogh Rasmussen said on Monday.
"To ensure that, we need a firm military response," he said in an interview with members of the European press association.
Failure to take military action, according to the alliance chief, would send a "very dangerous message" to the Assad regime and other U.S. adversaries in the region that chemical weapons use would be tolerated by the international community.
"Not to act is to act. Not to act would send a very dangerous message ... to dictators all over the world that they can use chemical weapons, and maybe other weapons of mass destruction, without any consequences," Rasmussen said.
To that end, he said there was "strong political support" among alliance members for military action in Syria. "Allies have consulted and I think there is consensus that we need a firm reply" to the Assad regime's alleged use of chemical weapons, he added.
Despite the growing number of foreign countries signing onto the White House statement, only on — France — has publicly agreed to provide military support for possible American-led action in Syria.
In Case You Missed It:
— White House insists Syria strikes do not need Hill approval
— Obama to press Senate GOP on Syria support
— Iran denies counterattack plans against US over Syria
— Rice: UN support for Syria mission 'not going to happen'
— US allies line up behind military action in Syria
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