Cohen's claim would contradict repeated denials by Trump, Donald Trump Jr., their lawyers and other administration officials who have said that the President knew nothing about the Trump Tower meeting until he was approached about it by The New York Times in July 2017.
Former New York City Mayor Rudy Giuliani, an attorney of President Donald Trump, took shots at former President Trump lawyer Michael Cohen's credibility, describing him as a "pathological manipulator" and "liar".
CNN cited anonymous sources saying Cohen was willing to share his information with Mueller, who is investigating possible collusion between Trump's campaign and Russian Federation.
"He can not be believed", Rudy Giuliani, a lawyer for Trump, said referring to Cohen.
"Colluding about Russians ― I'm not sure that's even a crime", Giuliani told CNN's Alisyn Camerota.
This week in the Russian Federation investigations: Michael Cohen goes rogue; what would it mean if it is determined he is telling the truth? What we have seen over the last day is a sharp turn in the pro-Trump message, from denying that any collusion took place to redefining what collusion means and whether it is okay.
Before, Trump blasted his former attorney for the secret recordings, suggesting that doing so might have been illegal.
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Then, citing sources with knowledge of the situation, CNN reported that Cohen claimed Trump knew in advance about the June 2016 meeting in Trump Tower in which Russians were expected to offer up dirt about Hillary Clinton to his campaign.
Cohen says on the tape with Trump that he's already spoken about the McDougal-story payment with the Trump Organization's finance chief, Allen Weisselberg, on "how to set the whole thing up".
In the CNN interview, Giuliani referenced a conflict so severe that if it were him, 'it's one that would have kept me out of the investigation.' But he wouldn't divulge more. Giuliani says that he is now of the opinion that Michael Cohen has lied his whole life.
"There are 12 others - maybe 11 or 12 others - out of the 183 in which the president is discussed at any length by Cohen, mostly with reporters", he added.
Jay Goldberg, another former Trump lawyer, argued Friday on CNN's "Erin Burnett Out Front" that Giuliani "immeasurably" damaged his case against Cohen with the sudden shift in tone.
Giuliani told Fox he has hired technicians to determine if someone tampered with the tape, which cuts off abruptly.
Cohen, whose business dealings are being investigated by the Federal Bureau of Investigation, has longtime dealings in the taxi industry and owns several medallions for New York City yellow cabs that allow them to pick up passengers on the street. As recently as May, Giuliani called Cohen "an honest, honorable lawyer". "You better buckle up buttercup because Mr. Trump's stupidity and disloyalty is about to catch up to him (and you)".