WASHINGTON – Colin Powell's ex-chief of staff said Thursday the former Secretary of State was lied to and manipulated by Vice President Dick Cheney into justifying the US invasion of Iraq.

The primary justifications offered by the Bush administration for invading Iraq were that Saddam Hussein possessed weapons of mass destruction and had possible links to Al-Qaeda. Both turned out to be false.

Iraqi defector "Curveball," ostensibly a source corroborating Hussein's biological and chemical weapons program, this week admitted he knowingly concocted the story in an effort to get rid of the dictator.

Lawrence Wilkerson, a retired Army Colonel who ran Powell's staff at the time, was asked by MSNBC's Cenk Uygur if he believes he and Powell were "flat-out lied to."

"I cannot come to any other conclusion," he responded, saying that some intelligence sources had warned Curveball may not be reliable. "I think there was some manipulation of the material and there was some outright lying."

Powell testified before the United Nations about Hussein's ostensible chemical and biological weapons, in a speech many believe was critical in justifying the invasion.

Asked by Uygur if he believes Cheney "manipulated" Powell into giving the speech, Wilkerson replied, "absolutely."

"The only member of this administration with any credibility is Colin Powell. He's got poll ratings like Mother Theresa," Wilkerson recalled telling his staffers at the time. "They're using him."

"One of my team said, 'Why is Powell doing this'?"

But Wilkerson lamented that even if Curveball had not existed, "we still would have gone to war with Iraq because George W. Bush and Dick Cheney were absolutely intent to do so."

This video is from MSNBC Live, broadcast Thursday.

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