On Thursday, the spotlight on Capitol Hill was focused squarely on former FBI Director James Comey. On Friday, it took President Donald Trump just seven words to sum up his thoughts.

"No collusion, no obstruction, he's a leaker," Trump defiantly said.

That response was part of an afternoon press conference where Trump disputed portions of the former FBI director's testimony.

One of the most noteworthy moments was an exchange with ABC News Chief White House Correspondent Jonathan Karl.

"(James Comey) did say under oath that you told him you said you hoped the Flynn investigation would let (it go)," Karl began to ask.

"I didn't say that," Trump retorted.

"So he lied about that?" asked Karl.

"Well, I didn't say that. I will tell you I didn't say that," Trump responded.

When Karl followed up and asked if President Trump would testify to that under oath with Robert Mueller, the Special Counsel to the Russia investigation, he doubled down.

"I would be glad to tell him exactly what I just told you," answered Trump.

Still, Trump's legal team is planning to file a complaint with the Department of Justice over Comey's leaking of memos of his conversations with the President.

But University of Texas History Professor Jeremi Suri believes Comey's in the clear.

"An official working for the government is allowed to keep unclassified notes on any meeting they have. And then once you no longer work for the government, your unclassified notes that you took on your own computer or on your own pieces of paper belong to you, and you have the right to reveal them to whoever you wish," Suri explained.

Suri also weighed in on Trump's willingness to testify under oath with Mueller.

"The president's statement today that he would not testify under oath is not legally binding. But he has now taken away the strongest argument that presidents have used in the past when not testifying oath, and that has been an argument about executive privilege," explained Suri.

Suri believed the president was not acting strategically when he asserted he'd testify under oath.

"I think he's emotionally reacting to testimony that has angered him. And this is a classic case where the reactions by the accused are getting the accused into more and more trouble," said Suri.

Still, Suri said there were a couple positives to emerge for Trump from Thursday's testimony.

"First of course, FBI Director's statement that Trump had not been under personal investigation. That's of course important. But also, the fact that the former FBI Director said he didn't really know the President's intentions. What the FBI Director said was that he felt pressured by the president, he felt directed by the president to limit a legitimate investigation of criminal behavior by Michael Flynn. But he never said that he thought the president had obstructed justice. When asked, he said it was not in his purview," Suri said.

However, Suri said those were somewhat negated by Trump's attacks on Comey's credibility. He believes the constant back-and-forth has made it difficult for the Trump administration to move forward.

"If this was a cloud over the White House (Thursday), it's now become a storm over the White House. It is eating up all of the time of the administration, which means they're on the defensive, and which also means they cannot pursue an alternative agenda which would get our attention away from this," explained Suri.

Despite his contentions with some of Comey's responses, Trump said he felt vindicated by the testimony.