INDIANOLA, Iowa – Vice President Joe Biden, speaking to a decidedly antiwar audience in Iowa on Sunday, played down the Obama administration's pledge to use military force to rid Syria of chemical weapons.

Biden, weighing a run for president in 2016, instead touted the U.S.-Russian diplomatic proposal for Syria to relinquish its chemical arsenal under international ­supervision.

"We're going to the United Nations with a resolution this week that will in fact call on the United Nations of the world to put pressure on Syria to have the confiscation and destruction of all those weapons," Biden told hundreds of Iowa's most devout Democrats at Sen. Tom Harkin's annual steak picnic and fall fundraiser.

Biden touched only lightly on the administration's continued insistence that "there are consequences should the Assad regime not comply." National public opinion polls show a military strike on Syria is unpopular, especially with Democrats.

The vice president worked to stoke hope that the ­diplomatic solution would work. Making the administration's first trip outside Washington since Obama's speech to the nation last Tuesday, Biden said Obama "is the reason the world is facing up finally, finally to this hideous prospect of this largest stockpile of chemical weapons."

There was no applause for his Syria comments, but listeners rose to their feet and cheered loudly when Biden ticked through the economic gains the country has made since Obama took office, improvements the vice president could benefit from, should they continue, if he runs for president in 2016.

Biden praised Harkin as the "conscience of the Senate," and the senator also raised hope the U.S.-Russian proposal would resolve the Syria issue, which is dominating world headlines.

"We didn't lose one American life," Harkin said, in introducing Biden. "That's leadership folks, that's leadership."

The hopeful tone in Biden's and Harkin's remarks came despite Obama's warning in an interview Sunday, "if diplomacy fails, the United States remains prepared to act."

Asked if he could rally leery Democrats should diplomacy fail, Biden told reporters briefly, "I think we're going to be OK."

Biden is considering running for the top job in the White House in 2016, and the crowd he mingled with Sunday, including many familiar with the two-time presidential candidate, would have the opening say during the state's caucuses.

With Hillary Rodham Clinton and Biden as the most prominent Democrats being discussed for their party's 2016 nomination, Obama said in a broadcast interview that he suspects both politicians would say it was "way too premature" to focus on the race.