David Jackson, and Kevin Johnson

USA TODAY

WASHINGTON — Former FBI director James Comey will soon testify in open session before the Senate Select Committee on Intelligence, following revelations Friday that President Trump told Russian leaders that Comey is a "nut job" who was adding pressure to the high-stakes investigation of possible interference in the 2016 election.

Comey, abruptly fired by Trump last week, has agreed to testify in public sometime after Memorial Day, the committee said in a statement.

“I hope that former Director Comey’s testimony will help answer some of the questions that have arisen since Director Comey was so suddenly dismissed by the President," said Sen. Mark Warner, D-Va., the committee's vice chairman. "I also expect that Director Comey will be able to shed light on issues critical to this Committee’s investigation of Russian interference in the 2016 election. Director Comey served his country with honor for many years, and he deserves an opportunity to tell his story. Moreover, the American people deserve an opportunity to hear it.”

A current White House official has drawn the scrutiny of federal investigators in the widening inquiry into Russia's interference in the 2016 election, a person familiar with the matter said Friday.

The person, who is not authorized to comment publicly, declined to identify the White House official. The development was first reported by the Washington Post.

The New York Times reported that Trump told Russian officials that Comey is a "nut job," and that dismissing him meant the pressure of the FBI's Russia probe has been "taken off."

White House officials did not deny either story, but only stressed that Trump and his staff had no collusion with Russia.

“As the President has stated before, a thorough investigation will confirm that there was no collusion between the campaign and any foreign entity," White House spokesman Sean Spicer said in response to the Post story that a White House official is now ensnared in the probe.

The president himself labeled the ongoing FBI probe a "witch hunt" this week after the Justice Department appointed a special counsel to oversee it in the wake of Comey's firing. Earlier this week, revelations that Comey kept memos detailing his conversations with Trump, including one in which the president apparently pressed his former FBI director to drop the inquiry into former national security adviser Michael Flynn, roiled Washington.

Sen. Richard Burr, R-N.C., chairman of the Senate Select Committee on Intelligence, said he hopes Comey's testimony brings some much-needed clarity.

“The Committee looks forward to receiving testimony from the former Director on his role in the development of the Intelligence Community Assessment on Russian interference in the 2016 US elections, and I am hopeful that he will clarify for the American people recent events that have been broadly reported in the media,” Burr said.

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As for the conversation with the Russians about Comey, Spicer essentially put the onus on the ex-FBI director.

"The President has always emphasized the importance of making deals with Russia as it relates to Syria, Ukraine, defeating ISIS and other key issues for the benefit and safety of the American people," Spicer said. "By grandstanding and politicizing the investigation into Russia's actions, James Comey created unnecessary pressure on our ability to engage and negotiate with Russia."

Spicer denied that Trump fired Comey to block the Russia investigation, saying, "the investigation would have always continued, and obviously, the termination of Comey would not have ended it. The real story is that our national security has been undermined by the leaking of private and highly classified conversations."

On May 10, the day after he fired Comey, Trump met with Russian Foreign Minister Sergey V. Lavrov and the Russian ambassador to the United States, Sergey I. Kislyak, in a meeting that has generated furious controversy.

The Times, citing a report on the meeting a source read to them, said that Trump told the Russians: “I just fired the head of the F.B.I. He was crazy, a real nut job ... I faced great pressure because of Russia. That’s taken off.” The president also reportedly said: “I’m not under investigation.”

The news said the documents that included the president's comments were based on notes taken from inside the Oval Office and have been circulated as the official account of the May 10 meeting. The report says one official read quotations to The Times, and a second official confirmed the broad outlines of the discussion. Other news reports also said that, during that same meeting, Trump discussed classified counter-terrorism information with the Russians.

Democrats said the new stories underscore their belief that Trump fired Comey in order to shut down the Russia probe. "If there was any question as to why Comey was really fired, @realDonaldTrump just answered it. As I said, Nixonian," said Sen. Bob Casey, D-Pa.

CNN reported that at one point during the 2016 campaign, Russian officials bragged in conversations that they had cultivated a strong relationship with Flynn and believed they could use him to influence Donald Trump and his team.

Citing two unidentified sources, CNN also reported that White House lawyers have begun researching impeachment procedures in an effort to prepare for what officials still believe is a distant possibility that Trump could have to fend off attempts to remove him from office.

White House officials believe the President has the backing of Republican allies in Congress and that impeachment is not in the cards, CNN reported. Even Democrats have tried to calm impeachment talk out of concern it is premature. But lawyers in the White House counsel's office have consulted experts in impeachment during the past week and have begun collecting information on how such proceedings would work, a person briefed on the matter told CNN.

Trump's glibness in private - and even public - statements has apparently caused his staff some consternation. The Wall Street Journal reported Friday that Trump’s aides have been pressing for more restraint by the president on Twitter, and some weeks ago they organized what one official called an “intervention.” Aides have been concerned about the president’s use of Twitter to push inflammatory claims, notably his unsubstantiated allegation from March that his Democratic predecessor, Barack Obama, had wiretapped his offices, the Journal reported.

In that meeting, aides warned Mr. Trump that certain kinds of comments made on Twitter would “paint him into a corner,” both in terms of political messaging and legally, an unnamed official told the Journal.

The top Democrat on the House Oversight and Government Reform Committee, Rep. Elijah E. Cummings, D-Md., called on Republican leaders to obtain the documents related to Trump's comments to Russian officials about Comey.

“This new report that President Trump openly admitted to the Russians that he ‘faced great pressure’ from the FBI’s criminal investigation that was ‘taken off’ when he fired Director Comey is astonishing — and extremely troubling," Cummings said in a statement.

"If these White House documents in fact exist memorializing the President’s statements to the Russians, the Oversight Committee needs to obtain copies immediately," he continued. "Chairman (Jason) Chaffetz should request these White House documents today and have his subpoena pen ready— just as he did earlier this week with the memos written by Director Comey.”

Contributing: Doug Stanglin