Trump said Friday that he was ready to testify under oath to special counsel Robert Mueller to deny former FBI chief James Comey's claim that the President asked him to back off his investigation into former national security adviser Michael Flynn.

"I didn't say that," Trump said of the claim about Flynn. Asked at a Rose Garden news conference whether he would testify under oath to Mueller to that effect, Trump replied: "100 percent." He added, "I would be glad to tell him exactly what I just told you."

The President's response could signal that he is convinced he has done nothing wrong and that Comey's testimony before the Senate Intelligence Committee on Thursday is no more than a lie.

Effectively, he was establishing a straight comparison between his word and Comey's on what went on in meetings and phone calls that made the former FBI chief so uncomfortable that he wrote down what happened.

Alternatively, it's possible that Trump may be calculating that there is no incriminating, objective proof about what occurred, leaving two irreconcilable versions of the same encounters.

CNN presidential historian Douglas Brinkley said that in two recent parallel situations in which Presidents Bill Clinton and Richard Nixon were accused of wrongdoing, there was accompanying incontrovertible evidence.

"In Clinton's case, there was Monica Lewinsky's blue dress. In Watergate, you had the White House tapes. We don't have the smoking gun evidence at this juncture," Brinkley said.

Significantly, Trump also used his appearance on Friday to deliver a broad hint that there are not, despite his earlier warning to Comey on Twitter, any tapes of their meetings and phone calls.

If such tapes exist, they could provide corroboration of either Trump's comments or Comey's account of their meetings, which the former FBI chief detailed in memos he gave to the special counsel, and which may add credibility to his version of events.

"You are struggling to find a scenario that actually makes sense because it stretches the imagination. What the President has done is put himself in a very precarious position," CNN legal analyst Laura Coates said on "New Day" on Saturday.

A court of law and the court of public opinion is likely to give some weight to Comey's memos of what he saw and heard, Coates said.

Comey testified on Thursday that he suddenly woke up in the middle of the night a few days after Trump tweeted that he better hope there were not tapes, with the same thought.

"Lordy, I hope there are tapes," Comey said at the hearing.

Trump's aggressive strategy since the Comey hearing would be a rash one indeed if such tapes, which the law would require him to hand over to investigators, are stashed away somewhere in the White House.

He told reporters on Friday that he would reveal if there are any tapes "over a fairly short period of time."

Then he added a teasing, cryptic comment that could indicate no such recordings exist.

"Oh, you're going to be very disappointed when you hear the answer, don't worry," Trump told reporters.

Still, Trump's approach represents a serious gamble, that could get him into deep legal and political waters if if backfires.

For one thing, if he were to go under oath with Mueller, he would not know for sure what kind of evidence the special counsel would bring to the table.

And depending on the conditions of the encounter, Trump might also open himself up to questioning on other issues, and risk saying something that may later turn out to be untrue and place himself in legal and political jeopardy.

"What was most interesting to me is his willingness to say 'I will say this under oath' ... that message is -- we will take the he said, he said ... and may the best, if you will, man win," Michael Zeldin, a former special assistant to Mueller when the special counsel headed the FBI, told CNN's Brooke Baldwin Friday.

Comey's verbatim notes written after his meetings with Trump would likely put his evidence in a more credible light than Trump's, should the President not have a record of his own conversations, Zeldin said.

"If there is a tie, I think that helps tip the tie toward the Comey side," he said.

Even so, it is questionable whether a GOP-controlled House of Representatives would move towards impeachment proceedings in a case simply based upon Comey's word against Trump's.

That may be the reason why the President, even if he is not telling the entire truth about his meetings with Comey, believes it is unlikely he will ever have to pay up on the bet that he made Friday.

And there is also no guarantee that Trump, despite saying he would testify before Mueller, will not change his mind about going under oath given the risks, or could be compelled to do so.