Russia has been reluctant to throw Assad, its longtime ally, under the bus. Moscow remains Syria's biggest foreign backer, providing the government with much of the arms and cash it needs to sustain the now two and a half year conflict. Russia has urged the United States to wait for the results of a U.N. investigation into the Aug. 21 attack before taking action.
Obama, however, made clear that he holds Russian intransigence accountable for the ongoing violence.
"I think that international action would be much more effective and ultimately we can end deaths much more rapidly if Russia takes a different approach to these problems," he said on Wednesday.
The White House expressed confidence that Congress will ultimately vote to authorize the use of force in Syria, even as the debate rages within both parties.
"I haven't done any vote counts," Deputy National Security Adviser Ben Rhodes said today. "We're very pleased with the trend lines."
Putin does not appear content to sit back and watch things happen. Earlier this week he backed a proposal for Russian lawmakers to lobby members of Congress ahead of the vote, urging them to vote no.
The White House is portraying the vote to authorize the use of force as critical to maintaining American leadership in the world.
"The world looks to the United States as a leader on these issues," Rhodes said.
"By necessity we have to be out front in terms of enforcement of international norms and were the United States to not play that role, there would be a significant vacuum in the international community," he added. "We do not want to send a message that the United States is getting out of that business in any way."