WASHINGTON — President Donald Trump said he was "100 percent" willing to testify under oath about his conversations with former FBI Director James Comey, and committed to do so if he were asked by special counsel Robert Mueller.

Speaking at a joint press conference in the Rose Garden with Romanian President Klaus Iohannis, Trump called Comey a "leaker" and maintained that the fired FBI director lied under oath about his claim the president asked him to drop the agency's investigation into former National Security Advisor Michael Flynn.

"I didn't say that," Trump said. There would be "nothing wrong if I did say" something regarding Flynn, Trump said "according to everybody I read today. But I did not say that."

Trump also denied that he asked Comey for a loyalty pledge, asking "who would ask a man to pledge allegiance under oath? I mean think of it. I hardly know the man. It doesn't make sense."

"No, I didn't say that and I didn't say the other," he said.

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Asked if he would testify under oath to Mueller, Trump said he'd be "glad" to tell him what he just told the press about Comey.

Regarding the possibility of tapes of the conversations between Trump and Comey — a possibility Trump himself raised on Twitter — he demurred.

“I’ll tell you about that maybe sometime in the near future," he said. "You're going to be very disappointed when you hear the answer, don’t worry," he previewed.

Trump said the former FBI director's exchange with lawmakers during Thursday's hearing before the Senate Intelligence Committee showed there was "no collusion, no obstruction."

He called the line of questioning regarding conversations between Trump and Comey "an excuse by the Democrats who lost an election that some people think they shouldn't have lost."

The stunning comments come after an early morning series of tweets from the president where he claimed "vindication" after Comey testified in front of the Senate one day earlier.

"Comey is a leaker," Trump wrote on Twitter, adding the fired FBI director gave "false statements and lies" Thursday — which would be considered perjury as Comey was under oath.

During his nearly two-and-a-half hours of testimony, Comey said Trump asked him for a pledge of loyalty, as well as urged him to "see a way out of" the FBI investigation into Flynn's conversations with Russia's ambassador.

Marc Kasowitz, Trump's outside counsel, rebutted the claims in a statement Thursday afternoon — pivoting to Comey's admission that he allowed the leak of information from his unclassified memos to news organizations in an attempt to trigger the appointment of a special counsel.

On Friday, NBC News learned Kasowitz would go a step further — seeking a leak complaint with the Department of Justice, according to a source close to the outside legal team.

The House Permanent Select Committee on Intelligence sent a letter to Comey on Friday asking for any notes or memos of conversations he had with the president. The committee also sent a letter to White House Counsel Don McGahn asking that he inform the committee whether the White House has ever had any recordings or memos of Comey's conversations with Trump.

If such material exists, they want the White House to provide it by June 23.

The Senate Judiciary Committee had previously asked Comey to provide those memos, but said it did not receive them. They are now asking Comey's friend, Columbia Law Professor Daniel Richman to provide copies of the memos.

During Thursday's congressional hearing, Comey testified "a good friend of mine who's a professor at Columbia Law School" was given the memo's notes to pass long to an unnamed reporter. Comey didn't identify Richman to the committee.