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WASHINGTON — Former FBI Director James Comey on Sunday dismissed the findings of a GOP report claiming there is no evidence President Donald Trump’s campaign colluded with Russians during the 2016 election. He added that, as a former prosecutor, he has “serious doubts” about Trump’s credibility as a potential witness.

Comey called the recently released report by Republicans on the House Intelligence Committee “a political document” during an interview on “Meet The Press.”

“That is not my understanding of what the facts were before I left the FBI and I think the most important piece of work is the one the special counsel's doing now,” Comey added.

Trump has seized on the report, tweeting that he believes it proves no collusion existed between his campaign and Russia, calling the investigations a “witch hunt” and “all a big Hoax by the Democrats based on payments and lies.”

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House Intelligence Committee rules that there was NO COLLUSION between the Trump Campaign and Russia. As I have been saying all along, it is all a big Hoax by the Democrats based on payments and lies. There should never have been a Special Counsel appointed. Witch Hunt! — Donald J. Trump (@realDonaldTrump) April 28, 2018

Democrats on the committee have called the report evidence of the lengths Republicans will go to shield Trump and his allies from scrutiny.

Asked whether the committee has served a good investigative purpose overall, Comey said, “not that I can see.”

The former FBI director also said politicization has “wrecked the committee, and it damaged relationships with the FISA Court, the intelligence communities. It's just a wreck.”

Comey did say, however, that when he led the FBI, his relationship with the committee chair, Rep. Devin Nunes, R-Calif., was “fine and professional” and that he believes Nunes and the ranking member, Rep. Adam Schiff, D-Calif., treated the agency fairly.

Comey’s interview came amid a national media blitz to promote his new book that is both a critique of Trump and defense of his time as FBI director.

“I have serious doubts about his credibility,” Comey said of Trump, adding that he worries about whether the president would be truthful under oath or not.

“Sometimes people who have serious credibility problems can tell the truth when they realize that the consequences of not telling the truth in an interview or in the grand jury would be dire,” Comey said. “But you'd have to go in with a healthy sense that he might lie to you.”

During his interview on Sunday, Comey also said he believes Special Counsel Robert Mueller is attentive to the political calendar and that those on Mueller’s team conducting the larger investigation into Russian attempts to interfere with American elections have not leaked what they know to the outside world.

“I'm sure he knows all of that,” Comey said when asked whether he thinks Mueller is mindful of the electoral lanscape. “He's definitely attentive to the calendar, and like all good prosecutors, wants to finish as quickly as he can."

Comey declined to answer multiple questions about details of the FBI’s Russia investigation and said he is skeptical about the publicly reported developments that have occured after he left his post.

“I love the media, but I always take it with a grain of salt. Because I know there are no leaks coming out of the Special Counsel's Office,” Come said. “So, by necessity, nobody who really knows what's going on is talking."