President Donald Trump on Friday called former FBI director James Comey an 'untruthful slime ball' and 'a PROVEN LEAKER AND LIAR' who 'should be prosecuted' for putting classified information in view of the media.

'James Comey is a proven LEAKER & LIAR. Virtually everyone in Washington thought he should be fired for the terrible job he did-until he was, in fact, fired,' Trump wrote in a pair of statements on Twitter. 'He leaked CLASSIFIED information, for which he should be prosecuted. He lied to Congress under OATH.'

'He is a weak and untruthful slime ball who was, as time has proven, a terrible Director of the FBI. His handling of the Crooked Hillary Clinton case, and the events surrounding it, will go down as one of the worst “botch jobs” of history. It was my great honor to fire James Comey!'

His extraordinary tweets, an unprecedented moment in American history, came after excerpts from a televised interview were broadcast on national television, with Comey saying it's 'possible' the most salacious detail in the anti-Trump 'dirty dossier' is true.

They also made their Internet splash the day after it was reported that Trump is poised to pardon Scooter Libby, a former vice presidential aide who was convicted of lying to the FBI and obstruction of justice during an investigation into a leak of the identity of a former covert CIA operative.

Comey said Friday in advance of next week's high-profile book release that despite having access to the nation's most sensitive law-enforcement intelligence for years, he still can't dismiss the possibility that Trump was involved with a 'golden showers' sex act with prostitutes five years ago.

President Donald trump declared all-out war Friday on former FBI director James Comey, calling him a 'slime ball' and saying he shoud be prosecuted for leaking information to the media

Comey gave an extraordinary interview to ABC in advance of his book release next Tuesday, saying an unproven story about the president cavorting with prostitutes in Moscow five years age might be accurate

Trump tweeted Friday that it was 'my great honor' to fire Comey in May 2017, and that he's 'a proven LEAKER & LIAR'

'I honestly never thought these words would come out of my mouth, but I don't know whether the current President of the United States was with prostitutes peeing on each other in Moscow in 2013,' he told ABC's 'Good Morning America' program in an interview broadcast Friday.

'It's possible, but I don't know.'

Trump's reference to leaking concerns Comey's admission during congressional testimony last year that he provided a longtime friend with a copy of memos he wrote after meeting with Trump in 2016 and 2017,m instructing him to circulate them among reporters.

Trump claimed Friday that the information was classified, a point that's still under debate in Washington.

The 'golden showers' accusation first came to light in an unproven dossier of opposition-research material paid for by the Democratic Party and the Hillary Clinton campaign and handed to the FBI during the 2016 presidential campaign.

Comey said he never told Trump that his political adversaries had funded the work, but warned him during a 'really weird' post-election meeting that the information was circulating at the top levels of the federal government.

Comey testified to Congress last year that he gave notes from his meetings with Trump to a friend and asked him to plant stories about them with reporters

The extraordinary moment in history had America's former top cop questioning the strength of the president's marriage because Trump thought there was 'a 1 per cent chance' the first lady might believe the salacious 'golden showers' tale

'It was almost an out-of-body experience for me,' he said. 'I was floating above myself looking down saying, "You're sitting here briefing the incoming President of the United States about prostitutes in Moscow".'

Comey's book, which goes on sale Tuesday, excoriates President Trump and is likely to be a best-seller

And he threw an elbow at the president's marriage, saying Trump suspected the first lady might choose to believe the dossier's worst conclusions about him – the hooker allegations.

'He said, "You know, if there's even a 1 per cent chance my wife thinks that's true, that's terrible",' Comey recalled.

'And I remember thinking, "How could your wife think there's a 1 per cent chance you were with prostitutes peeing on each other in Moscow?" I'm a flawed human being but there's literally zero chance that my wife would think that was true.

'So what kind of marriage to what kind of man does your wife think there's only a 99 per cent chance you didn't do that?'

Comey suggested the claim was still unproven but hedged his bets, saying only that 'when I got fired it was unverified.'

He said he never told Trump that he didn't believe it 'because I couldn't say one way or another.'

That hesitance, says the president's senior counselor Kellyanne Conway, suggests he developed an anti-Trump animus as a result of being pink-slipped, not while he was in government service.

'We find that Mr. Comey has a revisionist view of history and seems like a disgruntled ex-employee,' Conway told reporters outside the White House on Friday.

'After all, he was fired. It's not as if he came to the conclusions that are in his book while he was on the job as FBI director, in the presence, in the company of the president and said, "You know, I just must resign. I can't deal with this anymore. I must resign".'

Kellyanne Conway, among the president's most trusted advisers, told reporters Friday that Comey's anti-Trump conclusions came after he was unceremoniously fired, making him a 'disgruntled ex-employee'

The president handed Comey his walking papers last year, prompting him to write a dramatic tell-all – the first such book in history

Trump gave Comey the ax in May 2017. His principal response has been the book, due out Tuesday, titled 'A higher loyalty.' It represents the first pointed, opinionated tell-all volume by a former FBI director in history.

As newsrooms quickly devoured advance copies on Thursday, details began to filter out.

One describes Trump imperiously sitting behind the historic Resolute Desk in the Oval Office while he met with Comey instead of the usual, more casual setting of chairs at the opposite end of the room.

'[W]hen the president sits on a throne, protected by a large wooden obstacle, as Trump routinely did in my interactions with him, the formality of the Oval Office is magnified and the chances of getting the full truth plummet,' he writes.

Comey also carps about Trump's 'constant equivocation and apologies for Vladimir Putin.'

Elsewhere in his book, 'A Higher Loyalty,' Comey writes that White House Chief of Staff John Kelly told him shortly after hi was dismissed that Trump was a 'dishonorable' leader.

An 'emotional' Kelly, in Comey's telling, called him within minutes of his sudden dismissal and said he was 'sick' about the way Trump let him go.

Comey found out he was out of a job while he was delivering a speech to FBI agents in California and audience members told him his ouster was being flashed across TV news screens.

Kelly, Comey claims, said he 'intended to quit' in response and 'said he didn’t want to work for dishonorable people,' referring directly to the president.

The Republican Party has been gearing up for weeks to combat the accompanying PR blitz with a website, LyinComey.com. It lays out a set of talking points arguing that Comey lacks credibility and is out for revenge.

DailyMail.com obtained a copy of the White House's full-length talking points, which urge surrogates to emphasize 'gross inaccuracies' in Comey's congressional testimony.