James Comey's book 'A Higher Loyalty' likens Donald Trump to a mafia boss who is 'ego driven and about personal loyalty'

Casting him as a mafia boss-like figure, Mr Comey claims their interactions gave him 'flashbacks to my earlier career as a prosecutor against the Mob'

Former FBI Director James Comey calls Donald Trump as unethical and "untethered to truth" in his new book, in which he also describes the president’s leadership as "ego driven and about personal loyalty".

Set to be released next week, A Higher Loyalty adheres closely to Mr Comey's public testimony and written statements about his contacts with the president during the early days of the administration and his growing concern about the president's integrity.

Casting Mr Trump as a mafia boss-like figure, Mr Comey claims that interacting with the US leader gave him “flashbacks to my earlier career as a prosecutor against the Mob.”

Mr Trump sought to blur the line between law enforcement and politics and tried to pressure him regarding his investigation into Russian election interference, he claims.

The president, he says was obsessed with the prostitutes portion of the infamous dossier compiled by former British spy Christopher Steele.

It claimed that Mr Trump had watched the prostitutes urinate the same Moscow hotel suite that his predecessor Barack Obama and first lady Michelle had stayed in “as a way of soiling the bed.

Comey writes that the president tried to convince him it was not true by claiming he was “a germaphobe”, according to The Washington Post.

He later told him: “There’s no way I would let people pee on each other around me. No way," the newspaper reported.

The book includes strikingly personal jabs at Mr Trump that appear likely to irritate the president.

The 6-foot-8 Comey describes the US leader as shorter than he expected with a "too long" tie and "bright white half-moons" under his eyes that he suggests came from tanning goggles.

He says he made a conscious effort to check the president's hand size, saying it was "smaller than mine, but did not seem unusually so."

Mr Trump fired Mr Comey in May 2017, setting off a scramble at the Justice Department that led to the appointment of Robert Mueller as special counsel overseeing the investigation into Russian meddling in the US presidential election.

Mr Mueller's probe has expanded to include whether Trump obstructed justice by firing Mr Comey, an idea the president denies. Mr Trump has called Ms Comey as a "showboat" and a "liar."

The Republican National Committee is poised to lead the pushback effort against Mr Comey, who is set to do a series of interviews to promote the book, by launching a website and supplying surrogates with talking points that question the former director's credibility.

Mr Trump has said he fired Mr Comey because of his handling of the FBI's investigation into Hillary Clinton's email practices.

Mr Trump used the investigation as a cudgel in the campaign and repeatedly said Ms Clinton should be jailed for using a personal email system while serving as secretary of state.

Democrats, on the other hand, accused Mr Comey of politicising the investigation, while Ms Clinton herself has said it hurt her election prospects.

Mr Comey writes that he regrets his approach and some of the wording he used in his July 2016 press conference in which he announced the decision not to prosecute Ms Clinton.

But he says he believes he did the right thing by going before the cameras and making his statement, noting that the Justice Department had done so in other high profile cases.

Every person on the investigative team, Mr Comey writes, found that there was no prosecutable case against Clinton and that the FBI didn't find that she lied under its questioning.

Mr Comey's book will undoubtedly be heavily scrutinised by the president's legal team looking for any inconsistencies between it and his public testimony, under oath, before Congress.

They will be looking to impeach Mr Comey's credibility as a key witness in Mueller's obstruction investigation, which the president has cast as a political motivated witch hunt.

The Associated Press contributed to this report