Donald Trump in February asked James Comey, then head of the FBI, to halt an investigation into Michael Flynn, the former national security adviser, according to a memo that the law enforcement official wrote at the time.
During a private Oval Office meeting with Mr Comey, Mr Trump said: “I hope you can let this go,” in a reference to the FBI investigation into Mr Flynn, according to the memo.
The revelation marks the latest episode of a crisis that is consuming the White House. Mr Trump came under huge criticism last week when he fired Mr Comey whose agents are investigating Russian interference in the US election and alleged links between the Trump campaign and Moscow.
The emergence of the memo, which was disclosed by the New York Times, came one day after the Washington Post reported that Mr Trump had revealed top secret information on a potential Isis plot with the Russian foreign minister, Sergei Lavrov.
Mr Comey shared the memo — part of an extensive effort to document his interactions with the president — with top FBI officials, according to an associate who confirmed the existence of the memo and some of the lines that the FBI head wrote in it.
On Capitol Hill, Democrats pounced on the latest development about Mr Trump as evidence of a possible obstruction of justice. “If true, this is yet another disturbing allegation that the president may have engaged in some interference or obstruction of the investigation,” said Adam Schiff, the top Democrat on the House intelligence committee. “Enough is enough. Congress really needs to get to the bottom of this.”
Many Republicans hunkered down as the latest bombshell rocked Mr Trump’s young presidency, but some members suggested that the scandals were reaching a new level. John McCain, the Arizona Republican senator who has been one of the harshest GOP critics of Mr Trump, said the controversies engulfing the president were of “Watergate size and scale”, in a reference to the scandal that brought down Richard Nixon.
“Watergate was octopus-like, with so many tentacles it took an army of reporters to keep up. We’re not there yet, but Trump has one distinction,” said Larry Sabato, a politics expert at the University of Virginia. “We have never had a president so consumed by controversy and scandal this early in his term.”
In a worrying sign for Mr Trump that Republicans were becoming more nervous, Jason Chaffetz, the GOP head of the House oversight and government reform committee who has subpoena power, wrote to the FBI demanding “all memoranda, notes, summaries and recordings” regarding communications between Mr Trump and Mr Comey.
“@GOPoversight is going to get the Comey memo, if it exists. I need to see it sooner rather than later. I have my subpoena pen ready,” Mr Chaffetz tweeted.
A spokesperson for Paul Ryan, the Republican House speaker who was critical of Mr Trump during the campaign but who has been publicly supportive since his inauguration, said Mr Ryan supported the move by Mr Chaffetz to investigate the matter.
“We need to have all the facts, and it is appropriate for the House oversight committee to request this memo,” said spokesperson AshLee Strong.
The Comey memo is just the latest episode in a multi-faceted scandal about the role of Russia in the 2016 election that has engulfed Mr Trump and his top officials. In addition to the FBI probe, several Congressional committees are investigating the issue.
Mr Trump fired Mr Flynn in February, after 24 days on the job, following a Washington Post report that the retired general had misled Mike Pence, the vice-president, about conversations he had held with Sergei Kislyak, the Russian ambassador to the US.
The president frequently dismissed the FBI investigation, saying it was a “witch hunt” orchestrated by frustrated Democrats. But his comments have been contradicted by Mr Comey and other officials, who have publicly stated that the probe is serious.
The existence of the memo will increase pressure on Mr Comey to testify before Congress. He declined an invitation by the Senate intelligence committee to appear on Tuesday at a closed session, but is expected eventually to appear before lawmakers in a public hearing.
On Friday, Mr Trump implied that he may have taped his conversations with the FBI director. “James Comey better hope that there are no ‘tapes’ of our conversations before he starts leaking to the press!” Mr Trump tweeted.
The White House repeatedly has refused to confirm or deny whether Mr Trump has such tapes. If they exist, Congress should see them, Senator Angus King, an independent member of the Senate intelligence committee, said on Tuesday. “If there were tapes we need to have them . . . This is a very serious matter,” said Mr King.
Matthew Miller, a justice department spokesman in the Obama administration, last week said Mr Comey habitually kept written accounts of events he found potentially inappropriate.
The associate of Mr Comey told the Financial Times that, “as a general matter, there was a real effort to document” the exchanges with the president.
The White House denied Mr Comey’s account. “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,” it said. “This is not a truthful or accurate portrayal of the conversation between the president and Mr Comey.”
Senator Richard Burr, who leads the Senate intelligence committee’s Russia probe, said Mr Comey had not informed him of the exchange with the president.
Mr Trump abruptly fired Mr Comey last week, explaining the move as motivated by “this Russia thing”, a reference to the FBI investigation.
Andrew McCabe, the acting FBI director who had served as Mr Comey’s deputy, told Congress last week that “there has been no effort to impede our investigation to date”.
The memo quotes the president as saying: “I hope you can see your way clear to letting this go, to letting Flynn go.”
When Mr Trump added: “He is a good guy. I hope you can let this go,” Mr Comey replied: “I agree he is a good guy.”
By the time of the February 14 meeting, Mr Comey had become uneasy about Mr Trump’s invitations to meet at the White House, including for a private dinner in late January, according to James Clapper, the former director of national intelligence, who spoke with the FBI chief about it.
“He mentioned that he had been invited to the White House to have dinner with the president and he was uneasy with that,” Mr Clapper said, adding that Mr Comey feared “compromising the integrity of the FBI”.
As Washington struggled to make sense of the latest developments, there were hints of the fierce political combat that may lie ahead. Within hours of the first reports of Mr Comey’s memo, Mr Trump’s campaign arm sent out a fundraising appeal entitled “sabotage”, blaming the media and “special interests” for undermining the president.
“There are people within our own unelected bureaucracy that want to sabotage President Trump and our entire America First movement,” read the emailed alert, which suggested donations in amounts ranging from $1 to $2,500.
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