John Dowd, who formerly served as President Trump’s lawyer during part of the Russia investigation, dismissed special counsel Robert Mueller’s probe as “a terrible waste of time.”

“I know exactly what [Mueller] has,” Dowd told ABC News’ “ The Investigation” podcast. “I know exactly what every witness said, what every document said. I know exactly what he asked. And I know what the conclusion or the result is.”

Dowd referred to the investigation as “one of the greatest frauds this country’s ever seen” and said he does not expect Mueller to release a report on his findings into whether the Trump campaign colluded with the Russians during the 2016 election.

“There's no basis. There's no exposure. It's been a terrible waste of time,” he said.

Dowd’s comments are a departure from Justice Department officials pushing back on Trump’s repeated claims that the investigation is a "witch hunt."

"I do not believe special counsel Mueller is on a witch hunt," FBI Director Christopher Wray told Congress in June.

Acting Attorney General Matthew Whitaker, a Trump ally, defended Mueller while testifying to the House Judiciary Committee last week.

“I do believe he's honest," Whitaker said of the special counsel. "I have been on the record about my respect for Bob Mueller and his ability to conduct this investigation."

[Read more: Whitaker declines to say if the Mueller investigation is a 'witch hunt']

The veteran criminal defense lawyer resigned from his role as Trump’s lead attorney in March after butting heads with the president over how to cooperate with the special counsel.

Dowd said he did not want Trump to sit down for an interview because he was worried that the president would not be able to remember key details and would then be accused of perjury.

“What I was worried about is that he really couldn't do it,” Dowd said. “He couldn't do it.”

“In my questioning him or talking to him, you know, first question, easy. Second question, easy. Third question, he wasn't sure," Dowd continued. "And he doesn't like being unsure. So he'll guess. There's your trap, right there. It's not whether he lies or not ... It's not a matter of integrity. It's overload.”

Trump ended up sending written answers to Mueller late last year.

The attorney’s comments come as the Senate Intelligence Committee nears the end of its investigation into Russian interference in the election.

Sen. Richard Burr, R-N.C., the committee's chairman, said last week that their investigation has not found anything to suggest there was collusion.

Democratic Senate investigators told NBC News that the committee’s final report won’t be good for Trump, but it also won’t show direct evidence that Trump colluded with the Russians to win the election.