Former chief of the Federal Bureau of Investigation (FBI) James Comey recently blasted US President Donald Trump in an interview, saying the latter was "morally unfit" to hold the top post and that he treated women like "pieces of meat" and lied constantly and made the people of America believe them.
"I don't think he is medically unfit to be president".
Comey says that in his view a president must embody respect and adhere to the nation's core values, the most important being truth.
He later added that a Trump impeachment would let the American people "off the hook," stressing that he believes the president doesn't represent American values.
Comey also said that serving in Trump's administration poses a serious ethical dilemma.
Comey led the federal probe into Russian interference in the 2016 election before he was sacked by Trump.
In his first interview since being dismissed from his position last May, Comey defended his handling of an investigation into Hillary Clinton's use of a private email sever and portrayed Trump in a damning light. "It's possible", he said.
Mr Trump controversially fired Mr Comey from his position in May a year ago over his handling of a probe into possible collusion between the Trump campaign and Russian Federation during the 2016 US Presidential election.
Comey writes that his experiences with Trump gave him "flashbacks to my earlier career as a prosecutor against the mob".
Comey has been embroiled in controversy since reopening an investigation into whether Hillary Clinton's use of a private email server while USA secretary of state during Barack Obama's first term as president compromised national security.
"I mean, it's certainly some evidence of obstruction of justice".
In it, Comey compares Trump to a mafia don and calls his leadership of the country "ego driven and about personal loyalty". Comey, Trump tweeted, "was making decisions based on the fact that he thought she was going to win, and he wanted a job".
"It's illustrative of our polarization here that you've got the Trump camp, which I guess thinks I was trying to save Hillary Clinton". "These are more words I never thought I'd utter about a president of the United States, but it's possible".
On Sunday, before the ABC interview aired, Comey tweeted that his book draws on stories from his life and from lessons he has learned from others. There is no indication he is under investigation for doing so.
Mr Trump told Mr Comey that he had not stayed overnight in the Moscow hotel and that the claims related to the prostitutes were not true, Mr Comey said.
'I guarantee that there is no political influence in any investigation conducted by the Justice Department, or the F.B.I. - not just in this case, but in any case.