Senate Majority Leader Harry Reid is delaying a Senate test vote to authorize the use of force against the Syrian regime.

Reid said Monday evening that he would not take a procedural step that would have officially begun the Senate’s debate and set up a test vote on Wednesday. He added that he consulted with the president, fellow Democrats and the Republican leadership before slowing the timeline for the vote.

The shift came as major news networks aired interviews with President Barack Obama, who told NBC’s Savannah Guthrie that a Russian proposal to shift Syria’s chemical weapons cache to international control is a “potentially positive development."

"We are going to run this to ground. John Kerry will be talking to his Russian counterpart,” Obama said. “We're going to make sure that we see how serious these proposals are."

A Senate Democratic leadership aide told NBC News that the possibility of a diplomatic deal involving Russia is "a major factor" in explaining why Reid delayed the vote.

"Members want to see how things develop instead of being locked into a schedule," the aide said.

Obama has been lobbying lawmakers to support his push for limited intervention in Syria since he announced that he would seek congressional authorization for the move last week. But many members in both chambers are undecided or inclined to vote against the authorization, citing overwhelming public opposition to U.S. military action.

The president acknowledged to NBC News that he is not "confident" that he will have enough support in Congress to approve a resolution authorizing the use of force.

"I wouldn't say I'm confident," he said. "I'm confident that the members of Congress are taking this issue very seriously and-- and they're doing their homework and I appreciate that."

In a statement, Sens. Lindsey Graham, R-S.C., and John McCain, R-Ariz., said that only the threat of military action could push Syrian President Bashar Assad to give up control of the chemical weapons.

"For this reason, Congress should proceed with its plans to consider and vote on the authorization for use of force that is now before the Senate, and today's development should make Members of Congress more willing to vote yes," they wrote in a statement.