President Donald Trump called James Comey "cowardly" and said he thought any leaked information coming from the former FBI director could be "far more prevalent" than believed in his latest early morning Twitter jab.

"I believe the James Comey leaks will be far more prevalent than anyone ever thought possible. Totally illegal? Very 'cowardly!'" Trump tweeted Sunday morning.

I believe the James Comey leaks will be far more prevalent than anyone ever thought possible. Totally illegal? Very 'cowardly!' — Donald J. Trump (@realDonaldTrump) June 11, 2017

The tweet was the second social media lash out from Trump towards the fired FBI director since Comey's dramatic testimony before the Senate Intelligence Committee on Thursday.

And it comes a day after U.S. Attorney General Jeff Sessions said in a letter that he would be appearing before the committee on Tuesday to answer questions raised by Comey's recent testimony.

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On Friday, Trump tweeted called Comey a "leaker" and said that he felt "vindicated" by Comey's testimony, despite "so many false statements and lies."

Despite so many false statements and lies, total and complete vindication...and WOW, Comey is a leaker! — Donald J. Trump (@realDonaldTrump) June 9, 2017

Comey said Thursday that he began documenting his conversations with the president because he had a "gut feeling" Trump might lie about the nature of those meetings.

"I knew there might come a day when I needed a record of what happened," he said, adding he never felt the need to document his meetings with former Presidents Barack Obama and George W. Bush.

Comey also admitted that he had asked a "good friend" and confidante, Columbia Law Professor Daniel Richman, to leak a private memo of his conversations with Trump to the press after a previous tweet by the president.

"James Comey better hope that there are no "tapes" of our conversations before he starts leaking to the press!" Trump said in a tweet last month after Comey was fired.

James Comey better hope that there are no "tapes" of our conversations before he starts leaking to the press! — Donald J. Trump (@realDonaldTrump) May 12, 2017

Comey said during his testimony that he hopes there were recording of their interactions.

"Lordy, I hope there are tapes," he said.

Comey said that because his writings were unclassified, he felt he could share them with the media. Comey shared his memo after he was already fired, he said, adding that he hoped the leak "might prompt the appointment of a special counsel" into the investigation of Russian interference into the 2016 presidential campaign.

His hunch was apparently correct, as the very next day former FBI director Bob Mueller was appointed to be a special counsel overseeing the investigation.

Trump has publicly disputed some of Comey's version of events, including allegations that he asked Comey to potentially drop an investigation into former National Security Advisor Michael Flynn and Comey's recounting of a private White House dinner where he allegedly asked for "loyalty."

Comey said he responded that what he could offer was "honesty."

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Trump had said in an interview with NBC News' Lester Holt last month that Comey had dinner with him "because he wanted to stay" as director of the FBI.

Comey seemed to suggest during his testimony that Sessions had an undisclosed Russia issue that would have led to his eventual recusal from the investigation.

He said the FBI became "aware of facts that I can't discuss in an open setting that would make (Sessions') continued engagement in a Russia-related investigation problematic."

Speaking to lawmakers in a closed session later, Comey said he was talking about a story NBC News and other media outlets had already reported, the existence of classified intelligence suggesting an undisclosed meeting between Sessions and the Russian ambassador to the U.S. in April 2016 at the Mayflower Hotel in Washington, D.C.

Two sources familiar with what Comey said in the closed door gatherings told NBC News about the confirmation. A spokeswoman for Sessions has denied any such meeting took place.

"In light of reports regarding Mr. Comey's recent testimony before the Senate Select Committee on Intelligence, it is important that I have an opportunity to address these matters in the appropriate forum," Sessions said in his letter dated Saturday.

Trump has said he was "100 percent" willing to testify under oath about his interactions with Comey.

The president also took a swipe at the news media and Democrats Sunday morning.

The #FakeNews MSM doesn't report the great economic news since Election Day. #DOW up 16%. #NASDAQ up 19.5%. Drilling & energy sector... — Donald J. Trump (@realDonaldTrump) June 11, 2017