Lev Parnas, an associate of Rudy Giuliani, is willing to testify that aides to Intelligence Committee ranking member Rep. Devin Nunes (R-Calif.) canceled a 2019 trip to Ukraine to avoid notifying committee Chairman Adam Schiff (D-Calif.), CNBC reported Sunday.

Driving the news: Nunes has threatened to sue CNN and The Daily Beast for reporting allegations that he met with former Ukrainian prosecutor Viktor Shokin to discuss investigating former Vice President Joe Biden. He called the reports "false" and suggested the outlets may have committed crimes in reporting the claims by Joseph Bondy, Parnas' attorney.

Bondy alleged to CNN and the Washington Post that Parnas learned from Shokin that the former prosecutor met with Nunes in Vienna last December.

Schiff told CNN in a wide-ranging interview Sunday that the Intelligence Committee is seeking the records of and issued subpoenas for Parnas and Igor Fruman, who've both been indicted on campaign finance charges in a separate case.

"We have had discussions with the Southern District of New York in terms of Mr. Nunes' conduct. If he was on a taxpayer-funded CODEL — and I say if — seeking dirt on a potential Democratic candidate for president, Joe Biden, that will be an ethics matter. That's not before our committee."

— Adam Schiff's remarks on CNN

What they're saying: Per CNBC, Parnas would "tell Congress that the purpose" of Nunes' planned Ukraine visit "was to interview two Ukrainian prosecutors who claimed to have evidence that could help President Donald Trump’s reelection campaign."

Bondy told CNBC that Parnas wants to give House investigators "truthful and important information that is in furtherance of justice."

Nunes told Fox News' "Sunday Morning Futures" that Parnas is "a criminal" and that because the reports on him are "criminal in nature" and "so bad, so slanderous, we’ve got all the facts on our side and we are going to file in federal court."

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