Story highlights "I would hope that the President would apologize and move on," Flake said.

"But the accusations about the former president wiretapping, that's a serious allegation that you make about somebody," Flake said.

(CNN) Republican Sen. Jeff Flake said Monday that President Donald Trump should apologize to Barack Obama for alleging that the former president had ordered a wiretap of Trump Tower during the presidential campaign.

Flake, one of Trump's foremost Republican critics during the campaign, was asked on "Mac & Gaydos" on KTAR Arizona radio if he felt Trump should publicly admit he was wrong.

"I think that ought to happen and we ought to move on," Flake replied.

Asked later in the interview if his worst fears about Trump had been confirmed, Flake repeated his view that the President should apologize to his predecessor, though he said he didn't think that Trump's campaign had colluded with the Russians to defeat Hillary Clinton.

"Well, I'm not saying that I believe that the Trump campaign was involved with Russians on this. Frankly, my guess is that they didn't," Flake said. "I wouldn't want to believe that about anybody. But the accusations about the former president wiretapping, that's a serious allegation that you make about somebody. And that's not well-advised. And I would hope that the President would apologize and move on."

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