The origins of Special Counsel Robert Mueller's Russia investigation are built on a flimsy foundation, according to House Freedom Caucus Chairman Mark Meadows.

Rep. Meadows, R-N.C., reacted to reports Mueller could be called by Democrats to testify before Congress, in an appearance Thursday on "Hannity."

Meadows claimed the FBI and Justice Department knew shortly into the probe that former British spy Christopher Steele -- who compiled the anti-Trump dossier -- was not a "credible" individual, among other developments.

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"Within 60 days of them opening the investigation, prior to Bob Mueller coming on, the FBI and DOJ knew that Christopher Steele was not credible, the dossier was not true and [former Trump campaign associate] George Papadopoulos was innocent," the lawmaker claimed.

"Within 60 days of them opening the investigation, prior to Bob Mueller coming on, the FBI and DOJ knew that Christopher Steele was not credible, the dossier was not true and George Papadopoulos was innocent." — U.S. Rep. Mark Meadows, R-N.C.

"And so, when you look at that foundation, it's all built really on a foundation of sand, and that's going to start to show very soon."

The Great Smoky Mountains-area lawmaker added he believed the day of Mueller's public statement was the peak for the Democrats in regard to the investigation.

"The best day the Democrats had was a few days ago when Bob Mueller did his press conference," Meadows claimed. "That's the best day the Democrats have had and will have."

Host Sean Hannity added President Trump criticized Mueller for his appearance last week before reporters.

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Trump made those remarks to Fox News' Laura Ingraham in an interview that aired Thursday.

"He made such a fool out of himself. What people don't report is the letter he had to do to straighten out his testimony because his testimony was wrong, but Nancy Pelosi... doesn't talk about it," Trump told Ingraham.