Sam Nunberg, a former aide on the Trump campaign, did a 180 on Sunday on previous statements about President Donald Trump and a June 2016 Trump Tower meeting between Trump campaign officials and Russians.

Nunberg said he believed Trump's denials of knowing anything about the meeting in advance.

In March, Nunberg scoffed at such a denial and suggested Trump knew about the meeting "a week before" it took place.

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Sam Nunberg, a former aide on the Trump campaign, did a complete reversal Sunday regarding his stance on what President Donald Trump, then a candidate, knew about a June 2016 meeting at Trump Tower between top campaign officials and a Kremlin-connected lawyer offering dirt on Hillary Clinton.

Last week, CNN reported that Trump's former longtime lawyer Michael Cohen claimed Trump was told about the offer to have the meeting ahead of time and approved it. Cohen reportedly said he was one of several people in the room when Trump told his son Donald Trump Jr. to go ahead with it. The younger Trump was later one of several senior campaign officials, including Paul Manafort and Jared Kushner, who attended the meeting.

Trump and his lawyers maintain that he did not know about the meeting before it was first reported on last summer.

During an interview on NBC News' "Meet The Press," Nunberg said Sunday that he believed Trump over Cohen, though he never discussed the claims with Cohen.

"If Michael Cohen says now he knew about the Russia meeting in advance, I would believe Don Jr. and the president in light of learning Michael was taping conversations," Nunberg told the show's host, Chuck Todd.

Cohen's legal team last week released a secretly recorded conversation between Cohen and Trump about payments to Karen McDougal, a former Playboy model who says she had an affair with Trump years ago.

The conversation is believed to have happened shortly before the 2016 election, and Trump and Cohen appeared in the conversation to be discussing ways to pay for the rights to McDougal's story. She had been paid $150,000 by the publisher of a Trump-friendly tabloid, but her story was never published, a technique known as "catch and kill."

Nunberg also said Sunday that he hadn't discussed the Russia investigation with Trump but thought the president was complying with the special counsel Robert Mueller.

"I don't think the president has obstructed this investigation," Nunberg said. "He understands now that he cannot fire Robert Mueller, he cannot fire Jeff Sessions, he cannot fire Rod Rosenstein, because that would go down the Watergate model."

Nunberg described Trump as a good manager who didn't lie to him and "never, ever lied" about issues in his business.

"Everything was always done on the up-and-up — the president always would say everything has got to be legal, I'm not getting a fine, I don't want anything going on," Nunberg said.

Nunberg's statements on Sunday fly in the face of comments he made earlier this year when he went on a wild media blitz after being ordered to turn over emails and communications to Mueller as part of the Russia investigation.

In one interview, Nunberg told MSNBC that Trump "may have done something during the election," adding that he didn't know for sure.

At another point, Nunberg called Trump an "idiot."

He later told CNN that Mueller "thinks Trump is the Manchurian candidate," a phrase referring to a US politician who works, perhaps inadvertently, on behalf of a foreign government.

When CNN's Jake Tapper asked Nunberg whether he believed Trump's statement that he did not know about the June 2016 meeting in advance, Nunberg said he didn't.

"Jake, I've watched your news reports. You know it's not true," Nunberg said. "He talked about it a week before. And I don't know why he did this. All he had to say was: 'Yeah, we met with the Russians. The Russians offered us something, and we thought they had something, and that was it.' I don't know why he went around trying to hide it."

Nunberg testified to a grand jury in the Russia investigation in March.

Watch a clip of the interview below:

—Meet the Press (@MeetThePress) July 29, 2018