Updated at 2:20 p.m. ET
Undermining the prior rationale laid out by the White House, President Trump said he fired James Comey as FBI director without regard to the Justice Department's recommendation.
"Regardless of recommendation, I was going to fire Comey," Trump told NBC's Lester Holt in his widest-ranging remarks about his firing of Comey.
He added, "He's a showboat. He's a grandstander. The FBI has been in turmoil. You know that; I know that; everybody knows that. You take a look at the FBI a year ago — it was in virtual turmoil, less than a year ago. It hasn't recovered from that."
Raising more ethical questions, Trump admitted that he called Comey to find out whether he was under FBI investigation.
"If it's possible, will you let me know, am I under investigation?" Trump told Holt he asked Comey.
That's a remarkable admission, given the delineation most presidents and FBI directors are careful to try to draw. They don't want even the appearance of collusion or interference in what are supposed to be independent investigations, especially ones that might be related to themselves.
Comey was so careful, for example, to avoid the appearance of impropriety that during the Obama years, the 6-feet-8-inch Comey was sure to never play basketball with the then-president.
Trump also said that Comey told him two other times that he was not under investigation, once on the phone and once during a dinner that had been "arranged."
Trump initially claimed in the interview that Comey asked for the dinner to ask to stay on as FBI director. But Comey did not need to do that. He was appointed to a 10-year term in 2013.
The White House claimed Wednesday that morale was low at the FBI and was also a reason behind Comey's dismissal. That, however, was disputed by acting FBI Director Andrew McCabe, who said at a congressional hearing Thursday that Comey had the full confidence of the bureau.
On Wednesday, in brief remarks in the Oval Office, Trump told reporters that he fired Comey "because he wasn't doing a good job, simply. He was not doing a good job."
Trump abruptly relieved Comey of his duties Tuesday. The reasoning the White House officially gave — in writing — was Comey's handling of the Clinton email investigation based on a review by the deputy attorney general, Rod Rosenstein.
Vice President Mike Pence also said multiple times on Wednesday that Trump's dismissal of Comey was predicated on the recommendations of Rosenstein.
But both Democrats and Republicans are raising questions about the timing of Comey's firing. It comes just as the FBI appeared to be ramping up its investigation of Trump associates' ties to Russia.
White House spokeswoman Sarah Huckabee Sanders said the president has been thinking about firing Comey since November.
At Thursday's White House press briefing, Huckabee Sanders said she had a chance to speak with the president before she went out to the podium and said the "last straw that pushed" Trump was Comey's testimony before Congress on May 3.
Since the election, Comey has publicly confirmed that there was an ongoing FBI investigation into Trump associates and collusion with Russia; he disputed under oath the president's baseless claim that President Barack Obama ordered his team to be wiretapped; and on May 3, Comey said before Congress that he was "mildly nauseous" that he may have swung the election after coming forward days before the election to say that he was reopening the Clinton email investigation.
Comey also requested significantly more resources for the Russia investigation from Rosenstein and briefed key senators on that request Monday, the same day another congressional hearing on the Russia investigation took place at which former national security adviser Michael Flynn's and the White House's conduct was the central focus.
Comey was fired the next day, which was dominated by bad headlines for Trump on why Flynn was kept on for 18 days after Sally Yates, the former acting attorney general, told White House counsel Don McGahn that Flynn had been compromised.
NPR's Jessica Taylor contributed.