Comey, speaking to ABC News' George Stephanopoulos, touched on many of the scandals that have plagued the Trump administration over the past 16 months, including the Russia dossier and the litany of sexual misconduct allegations leveled at the president.
"A person who sees moral equivalence in Charlottesville, who talks about and treats women like they're pieces of meat, who lies constantly about matters big and small and insists the American people believe it, that person's not fit to be president of the United States, on moral grounds," Comey said.
Highlights from the interview include:
- Trump may be vulnerable to Russian blackmail. "I think it's possible. I don't know. These are more words I never thought I'd utter about a president of the United States, but it's possible."
- The president "treats women like they're pieces of meat."
- In regards to Trump asking Comey to drop his investigation into former national security adviser Michael Flynn, there was "certainly some evidence of obstruction of justice."
- Comey said Trump was "of above average intelligence who's tracking conversations and knows what's going on."
- "I don't think he's medically unfit to be president. I think he's morally unfit to be president."
- He said Trump "will stain everyone around him. And the question is, how much stain is too much stain..."
- Trump was obsessed with disproving allegations that he paid prostitutes to urinate on a bed in a Moscow hotel room. Comey recalled the president asking "Do I look like a guy who needs hookers?"
The interview comes just days before the release of his highly anticipated book, A Higher Loyalty: Truth, Lies, and Leadership, which has already sold close to 200,000 copies.
As the interview continued, Comey appeared to have no fondness for the man who fired him last May.
"The challenge of this president is that he will stain everyone around him," he told Stephanopoulos. "And the question is, how much stain is too much stain and how much stain eventually makes you unable to accomplish your goal of protecting the country and serving the country?"
The former FBI director said, however, he'd still be working for the government had he not been removed. "I was dreading it," Comey said, noting he'd be "an unhappy F.B.I. director, but in a way proud of the organization and in my role in trying to protect it."
Comey also recounted his conversation with Trump in which he said the president asked him to drop an investigation into then-national security adviser Michael Flynn. Trump has denied doing so and threatened to release "tapes" of the conversation to prove so.
Comey reiterated that he hoped such tapes existed and said the secretive nature of the meeting might imply Trump knew he was flouting convention. "If he didn't know he was doing something improper, why did he kick out the attorney general and the vice president of the United States and the leaders of the intelligence community? I mean, why am I alone?"
"I'd be a crazy person to make it up," he continued.
Stephanopoulos also asked if Comey believed the president obstructed justice, to which he replied: "Possibly."
"I mean, it's certainly some evidence of obstruction of justice. It would depend and ― and I'm just a witness in this case, not the investigator or prosecutor ― it would depend upon other things that reflected on his intent."
Among the more salacious topics during the interview focused on the infamous Steele dossier that was compiled by a former British spy and alleged that footage exists of Trump watching prostitutes urinating in a Moscow hotel suite. Comey informed Trump about the allegations in private before his inauguration several times, and he writes in his book that Trump was obsessed with disproving them.
On Sunday, he said he was unsure if the rumors were true, but said they left the president open to blackmail by the Russian government.
"I honestly never thought these words would come out of my mouth, but I don't know whether the ― the ― current president of the United States was with prostitutes peeing on each other in Moscow in 2013," Comey said. "It's possible, but I don't know."
Stephanopoulos also asked if he thought Russia had "something" on the president.
"I think it's possible," he said. "I don't know. These are more words I never thought I'd utter about a president of the United States, but it's possible."
The interview prompted immediate reactions from Republican leadership.
"James Comey's publicity tour reaffirms that his true higher loyalty is to himself," Ronna McDaniel, the chair of the Republican National Committee, said in a statement. "The only thing worse than Comey's history of misconduct is his willingness to say anything to sell books. He has no credibility and President Trump was right to follow through on the bipartisan calls for him to be fired."
As the reviews on Comey's tell-all began to pour in, Trump immediately fired back on Twitter, calling the man an "untruthful slimeball" and intimating that he should be jailed for his actions at the helm of the FBI. White House press secretary Sarah Huckabee Sanders later said Comey would "be forever known as a disgraced partisan hack that broke his sacred trust with the president of the United States."
Trump unleashed another wave of fury on Twitter early Sunday, just hours before the ABC interview was set to air, accusing the former FBI chief of pushing "many lies" and predicting Comey would go down as the "WORST FBI Director in history, by far!"
Comey responded to the tweets with a message of his own, saying his book was "about ethical leadership & draws on stories from my life & lessons I learned from others."
He continued: "3 presidents are in my book: 2 help illustrate the values at the heart of ethical leadership; 1 serves as a counterpoint."
"I hope folks read the whole thing and find it useful."