Calling the US "the anchor of global security," Obama in a televised address offered moral, political and strategic arguments for being ready to launch limited military strikes while trying to negotiate a diplomatic solution.
Obama termed the Russian proposal an "encouraging" sign to place Syria's chemical weapons under international control.
Obama said that he has asked his military to continue maintaining its aggressive posture in the region pending a diplomatic solution to the Syrian crisis.
He, however, said it is too early to tell if the Russian effort would succeed.
"It's too early to tell whether this offer will succeed, and any agreement must verify that the Assad regime keeps its commitments. But this initiative has the potential to remove the threat of chemical weapons without the use of force, particularly because Russia is one of Assad's strongest allies," he said.
"I have therefore asked the leaders of Congress to postpone a vote to authorise the use of force while we pursue this diplomatic path. I'm sending Secretary of State John Kerry to meet his Russian counterpart on Thursday, and I will continue my own discussions with (the Russian) President (Vladimir) Putin," Obama said in his address to the nation.
The 15-minute nationally televised speech initially was planned as Obama's final push to win support from a sceptical public and Congress for his planned attack on Syria for what his administration calls a major chemical weapons attack on August 21 that killed more than 1,400 people in suburban Damascus.
