Former FBI Director James Comey wrote in a memo that President Donald Trump asked him to end the investigation of national security adviser Michael Flynn, according to a sources familiar with the matter.
Comey was so appalled by the request that he wanted to document it, sources said. Comey shared it with FBI senior officials, according to sources.
"I hope you can let this go," Comey wrote, quoting the President. CNN has not viewed the memo but sources described it to CNN.
The memo is the clearest sign yet of potential interference by Trump with the investigation into whether members of his campaign team colluded with Russian officials.
"Three words: obstruction of justice," said CNN's senior legal analyst Jeffrey Toobin on Tuesday. "Telling the FBI director to close down an investigation of your senior campaign adviser for his activities during your campaign for president, if that's true, that is obstruction of justice."
" 'Close it down' is an instruction to stop investigating President Trump's campaign. Richard Nixon was impeached in 1974 for telling the FBI to stop an investigation of his campaign. That's what Watergate was," Toobin added. "If (Comey's) telling the truth, I don't know how anyone can see this comment as anything but obstruction of justice."
Writing the memo was "not out of character," especially if he was concerned about the legality or moral issues, according to a former Justice Department official.
The New York Times first reported news of the memo.
Multiple White House officials refuted the claim on Tuesday, including one who said a "conversation of that nature" did not happen.
"While the President has repeatedly expressed his view that General Flynn is a decent man who served and protected our country, the President has never asked Mr. Comey or anyone else to end any investigation, including any investigation involving General Flynn," a White House official said in a statement. "The President has the utmost respect for our law enforcement agencies, and all investigations. This is not a truthful or accurate portrayal of the conversation between the President and Mr. Comey."
'A number of memos'
Comey was in the Oval Office briefing the President along with the vice president and attorney general on February 14, according to a source close to Comey who has a copy of the memo. After the briefing, Trump "asked Sessions and Pence to leave," the source told CNN.
According to a memo, Comey wrote about the encounter and shared with confidantes, the President said: "I hope you can see your way clear to letting this go, to letting Flynn go. He is a good guy. I hope you can let this go."
He told Comey that Flynn hadn't done anything wrong.
Comey was "concerned" that the President was trying to "stop the investigation," the source told CNN. "He wrote a number of memos, a great many if not all were about contacts with Trump -- particularly the ones that made him feel uneasy."
The source did not know how many memos Comey had written.
The source said that Comey hopes the President's threats about "tapes" of their conversations indicate there are actually recordings of their conversations.
"He would love to have them," the source said. "One of his reasons for writing these memos is the concern this couldn't be corroborated -- but that could be met if there are tapes."
Loyalty to Flynn
Trump has looked to stay loyal to Flynn, despite the fact that he fired his top national security aide in February after it became clear that he did not properly disclose the nature of conversations he had with Russian officials.
Trump, in a series of public comments and interviews, has suggested that Flynn was being mistreated and has heralded him as a good man.
"Gen. Flynn is a wonderful man. I think he has been treated very, very unfairly by the media, as I call it, the fake media in many cases," Trump said in February. "And I think it is really a sad thing that he was treated so badly."
McCabe testimony: FBI investigations unimpeded by Comey firing
In Senate testimony last Thursday, acting FBI Director Andrew McCabe told lawmakers that despite Comey's firing, there had been "no effort" to impede the FBI's ongoing investigations.
During an intelligence committee hearing, Sen. Marco Rubio, R-Florida, asked: "Mr. McCabe, can you, without going into specifics of any individual investigation, I think the American people want to know, has the dismissal of Mr. Comey in any way impeded, interrupted, stopped or negatively impacted any of the work of any investigation or any ongoing projects at the Federal Bureau of Investigations?"
McCabe, who was filling in for Comey, responded: "As you know senator, the work of the men and women of the FBI continues despite any changes in circumstance, any decisions, so there has been no effort to impede our investigation to date. Simply put, sir, you cannot stop the men and women of the FBI from doing the right thing, protecting the American people and upholding the Constitution."
Lawmakers want to hear from Comey
Reaction from Capitol Hill was swift, with Republicans and Democrats alike demanding answers from Comey.
Sen. Lindsey Graham, a South Carolina Republican, said Tuesday that the former FBI director should testify before Congress about his conversation with Trump.
And Sen. Dianne Feinstein told reporters that she "absolutely" thinks Comey should testify before the full Senate Judiciary Committee on the conversation.
"I believe we should begin to hold hearing as a full committee on this," she said.