President Donald Trump denied on Friday that he had told then-FBI chief James Comey he hoped Comey could let go an investigation into a former national security adviser, adding he was willing to give his version of events under oath.

"I didn't say that," Trump told reporters when asked about Comey's account relating to the investigation into former national security adviser Michael Flynn. Comey, fired by Trump last month as FBI director, gave the account in sworn testimony to a Senate panel on Thursday.

Asked if he would be willing to give his version of events under oath, Trump replied: "100 percent."

Comey's testimony, according to Trump, also showed that he had not attempted to obstruct justice in conversations the two officials held.

"Yesterday showed no collusion, no obstruction; he's a leaker," Trump said of Comey and his testimony during a joint news conference with Romanian President Klaus Iohannis in the White House rose garden. "But we want to get back to running our great country."