(Peter Stevenson/The Washington Post)

At least three senior White House officials, including the top lawyer for the National Security Council, were involved in the handling of intelligence files that were shared with the chairman of the House Intelligence Committee and showed that Trump campaign officials were swept up in U.S. surveillance of foreign nationals, according to U.S. officials.

The White House role in the matter contradicts assertions by the committee’s chairman, Rep. Devin Nunes (R-Calif.), and adds to mounting concerns that the Trump administration is collaborating with the leader of the House Intelligence Committee’s investigation of Russian meddling in the 2016 election.

Though White House officials have refused to answer questions about the documents shared with Nunes, the White House said in a letter to the House committee Thursday that it had “discovered documents” that might show whether information collection on U.S. persons was mishandled and was prepared to show them to lawmakers.

One of those involved in procuring the documents cited by Nunes has close ties to former national security adviser Michael Flynn. The official, Ezra Cohen-Watnick, survived a recent attempt to oust him from his White House job by appealing to Trump advisers Jared Kushner and Stephen K. Bannon, the officials said.

(Reuters)

The materials unearthed by Nunes have been used to defend President Trump’s baseless claims on Twitter that he had been wiretapped at Trump Tower under a surveillance operation ordered by then-President Barack Obama. FBI Director James B. Comey and others have said that claim is false.

Nunes reviewed the material during a surreptitious visit to the White House grounds last week. He then returned the next day in a visit he said was arranged so that he could brief Trump on what Nunes depicted as potential abuses­ by U.S. spy agencies brought to his attention by an unnamed source.

Nunes and White House press secretary Sean Spicer have repeatedly refused to answer questions about the identities of those involved in unearthing the intelligence reports or arranging for Nunes to review them at the White House complex — although Nunes at one point said his source was not a member of the White House staff.

That assertion is under new scrutiny after U.S. officials confirmed that three senior officials at the National Security Council — considered part of the White House — played roles in the collection and handling of information shared with Nunes.

The officials said that the classified files were gathered by Cohen-Watnick, the senior director for intelligence at the National Security Council.

After assembling reports that showed that Trump campaign officials were mentioned or inadvertently monitored by U.S. spy agencies targeting foreign individuals, Cohen-Watnick took the matter to the top lawyer for the National Security Council, John Eisenberg.

The third White House official involved was identified as Michael Ellis, a lawyer who previously worked with Nunes on the House Intelligence Committee but joined the Trump administration as an attorney who reports to Eisenberg. Ellis and Eisenberg report to the White House counsel, Donald McGahn.

House Intelligence Committee Chairman Rep. Devin Nunes (R-Calif.) leaves the House floor on March 29. (Aaron P. Bernstein/Reuters)

The involvement of Ellis and Cohen-Watnick was first reported Thursday by the New York Times.

A spokesman for the NSC declined to comment. Jack Langer, a spokesman for Nunes, said the chairman “will not confirm or deny speculation about his source’s identity.” Langer also said that Nunes “will not respond to speculation from anonymous sources,” despite Nunes’s insisting on the anonymity of his own source.

Nunes, who served as an adviser to the Trump transition team, said the files he reviewed had made him concerned that U.S. intelligence agencies had mishandled information on members of the Trump campaign, although Nunes acknowledged that he saw no evidence of illegality.

He appeared to be referring to cases­ of “incidental” collection on U.S. persons, which generally occur when foreign officials being monitored by U.S. spy agencies either mention an American or communicate with one. The identities of those Americans are supposed to be masked in any intelligence reports disseminated in the U.S. government.

Nunes said that most names were masked in the files he reviewed but that he could still identify Trump campaign officials from context.

Cohen-Watnick gathered the cases­ of incidental collection on Trump campaign operatives after arriving at the NSC. One official said Cohen-Watnick did so as part of research unrelated to Trump’s wiretapping tweet. Instead, the official said, Cohen-Watnick was assembling materials out of concern that intelligence information on U.S. persons was being shared too widely and that unmasking rules were being abused.

The U.S. official said Cohen-Watnick was not involved in showing the material to Nunes, didn’t clear Nunes onto the White House grounds, didn’t review the material with Nunes and wasn’t even aware that the material was going to be shared with the committee chairman.

Even so, White House officials appear to have recognized the value of Cohen-Watnick’s material in defending Trump from criticism for his false accusation that he had been wiretapped by Obama.

U.S. officials declined to say who had contacted Nunes or arranged his White House visits, except to note that Cohen-Watnick had brought his findings to the attention of Eisenberg and that Ellis works for Eisenberg.

Cohen-Watnick was brought into the administration by Flynn, a former Defense Intelligence Agency director who was fired after it was exposed that he had misled Vice President Pence and others about his contacts with Russian Ambassador Sergey Kislyak.

During a preliminary meeting this month to discuss the possibility of Flynn testifying before Congress, Flynn’s attorney said he wanted to explore the possibility of his client receiving full immunity in exchange for his participation.

Intelligence committee lawyers responded to the attorney by saying that immunity request, which was first reported by the Wall Street Journal, was premature. “That’s not on the table,” an official said. “We aren’t entertaining immunity for anybody.”

Flynn frequently battled with the CIA, which mounted a failed effort to have Cohen-Watnick removed from his job.

After Flynn was replaced by H.R. McMaster, some in the CIA made it known to him that the agency would prefer someone else in Cohen-Watnick’s job. Early this month, McMaster interviewed the agency’s suggested candidate, senior CIA analyst Linda Weissgold, and informed Cohen-Watnick that he was being moved to another position.

Cohen-Watnick consulted Kushner and Bannon, Trump’s chief White House strategist. After Kushner and Bannon spoke with Trump over the March 11-12 weekend, Cohen-Watnick was back in place.

Within days, a CIA detailee to the NSC working under Cohen-Watnick was told without explanation to clear out his desk and return to the agency. The agent, a former and future covert operative whose name is being withheld by The Washington Post at the request of the CIA, was on a standard two-year rotation to the White House.

In its letter to the committee, the White House repeated calls for it to investigate leaks that have led to media reports about contacts by Trump associates with Russian operatives. In particular, it referred to a March 2 MSNBC interview with former Obama Defense Department official Evelyn Farkas, which has suddenly become a leading element in White House pushback against the Russia allegations and evidence of Trump’s claim that the Obama administration has actively sought to undermine his presidency.

The interview took place after the New York Times reported that the Obama White House, fearing the new administration would sweep it under the rug, had spread information about Russian efforts to undermine the presidential election. Farkas said, “I was urging my former colleagues and . . . the Hill people, get as much information as you can, get as much intelligence as you can, before President Obama leaves the administration.”

“That’s why there were so many leaks,” said Farkas, now a senior fellow at the Atlantic Council.

While her comments were widely ignored when initially broadcast four weeks ago, the MSNBC clip suddenly appeared Tuesday on conservative websites and subsequently on Fox News and other television outlets. In a Hugh Hewitt radio interview Wednesday evening, White House Chief of Staff Reince Priebus said that its relevance to “surveillance of Trump transition team members is something that we need to figure out.”

Spicer, referring to the Obama administration, said the Farkas comment constituted an admission “on the record that this was their goal, to leak stuff.”

Farkas, in an interview with The Post, said she “didn’t give anybody anything except advice,” was not a source for any stories and had nothing to leak. Noting that she left government in October 2015, she said, “I was just watching like anybody else, like a regular spectator” as initial reports of Russia contacts began to surface after the election.

As a former staff member of the Senate Armed Services Committee, and a former Defense official involved with Russian affairs, she said she “got worried” that the Obama White House was not briefing Congress on what it knew. “I know how the Russians operate,” she said, and called former colleagues to make sure Congress was being informed.

Adam Entous, Abby Phillip, Jenna Johnson, Philip Rucker, Karoun Demirjian and Julie Tate contributed to this report.

This story has been updated.