Sen. Rand Paul charged in a bombshell tweet late Wednesday that former CIA Director John Brennan "insisted that the unverified and fake Steele dossier" be included in a classified intelligence community report on Russian interference in the 2016 election.

Paul (R-Ky.) said Brennan must testify under oath immediately, as Republican lawmakers continue to aggressively seek out the origins of the Trump-Russia collusion narrative and what role the dossier played in the Russia probe.

On "Fox & Friends" Thursday, Paul revealed that his source told him that the intelligence community under then-President Obama -- including Brennan, then-Director of National Intelligence James Clapper and then-FBI Director James Comey -- were frustrated because they had the dossier but nobody believed it was credible.

"They wanted to somehow get this information out ... that even the media wasn't publishing. Nobody would publish it because it was so scandalous, unverifiable and, likely, fiction," Paul said.

He claimed that's why Brennan pushed to have the dossier attached to an intelligence report, so it would appear more justified and credible.

"This is a big circle. So when John McCain is given the dossier, it's given to him by people who may have leaked it to our government to John McCain so John McCain can give it back to the FBI," Paul said. "It's a crazy circle all trying to justify something that wasn't true."

He called out the "extraordinary power" and "extraordinary corruption" of some in the intelligence community, saying they attempted to bring down a sitting president, which must never happen again.

Paul said he wants to know when Obama found out about the dossier and what he recommended.

Watch the "Fox & Friends" interview above.

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