President Donald Trump's former personal attorney, Michael Cohen, now says Trump knew about the 2016 Trump Tower meeting with the Russians that Trump's son, Donald Trump Jr., attended in hopes of acquiring compromising information on then-Democratic presidential nominee Hillary Clinton, according to CNN.

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CNN, citing a source familiar with the case, reported that Cohen is willing to tell special counsel Robert Mueller what he knows about the meeting.

He reportedly said he was present when then-candidate Trump was told about the Russians' offer and that Trump approved of the meeting, according to CNN sources, but Cohen does not have any evidence to back up his claim.

Trump's current attorney and former New York Mayor Rudy Giuliani said in an interview on CNN that Cohen is not believable.

“He’s certainly a source that is not credible,” Giuliani said.

"I expected something like this from Cohen. He's been lying all week. He's been lying for years," he said.

Trump, his son and others have repeatedly denied that the president had any knowledge of the 2016 meeting. In a series of tweets Friday morning, Trump criticized “the highly conflicted Robert Mueller and his gang of 13 Angry Democrats,” and repeated that he had knowledge of the meeting.

“It sounds to me like someone is trying to make up stories in order to get himself out of an unrelated jam,” the president tweeted.

Trump Jr. also testified to that under oath last December before a closed-door Senate committee investigating Russian interference in the 2016 presidential election, denying any wrongdoing.

“I did not collude with any foreign government and did not know anyone who did,” Trump Jr. testified, according to a transcript of his testimony, which was released in May.

“That was the end of it and there was no further contact or follow-up of any kind,” Trump Jr. said of the June 9, 2016 meeting. “My father knew nothing of the meeting or these events.”

Trump Jr. first publicly said that the meeting was about American adoption of Russian children, when the New York Times approached him about the meeting, which was also attended by President Trump's son-in-law Jared Kushner and his campaign manager at the time, Paul Manafort, in addition to several Russians.

Cohen, meantime, is facing legal troubles of his own and is under investigation by federal prosecutors in New York.