KNOXVILLE, IA (CNN) Pete Buttigieg on Sunday knocked Joe Biden for his vote in favor of authorizing military force against Iraq in 2002 when the former vice president was a senator, calling it "the worst foreign policy decision made by the United States in my lifetime."

"Well, I certainly respect the Vice President, but this is an example of why years in Washington is not always the same thing as judgment," Buttigieg told Iowa Public Television in a Sunday morning interview while campaigning in the state. "He supported the worst foreign policy decision made by the United States in my lifetime, which was the decision to invade Iraq."

Biden has faced criticism for his support of the war , though he later became a vocal critic of the conflict. In 2002, then a senator from Delaware, Biden voted in favor of the Iraq War resolution, which authorized President George W. Bush to attack Iraq if Saddam Hussein refused to give up weapons of mass destruction as required by United Nations resolutions. The Senate passed the resolution in a 77-23 vote, with support from both sides of the aisle.

The intelligence used by the Bush administration that claimed Iraq possessed weapons of mass destruction has since been discredited, and support for the war has declined in the years since it began.

Biden has said his vote for the Iraq War resolution was a "bad judgment," and that he "was outspoken as much as anyone at all in the Congress and the administration," in the lead up to the 2003 invasion -- though a CNN fact check into Biden's claims found that Biden defending his vote well into 2003

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