Former FBI Director James Comey lambasted President Donald Trump in an exclusive interview on Sunday night, calling Trump ill-suited for his role as leader of the country and revealing new details about his campaign’s alleged collusion with Russia.

James Comey ABC Interview On Trump

The interview with ABC’s George Stephanopoulos was meant to serve as part of a tour for Comey’s new book A Higher Loyalty, which explains just how much of a threat to the nation the conservative former FBI director — whom Trump fired in May 2017 — believes the president represents.

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“Our president must embody respect and adhere to the values that are at the core of this country,” Comey told Stephanopoulos. “The most important being truth. This president is not able to do that. He is morally unfit to be president.”

Comey went on to call Trump a “stain” on everyone he worked with, and also took aim at the former Apprentice star’s mistreatment of women, whom the former FBI director said Trump viewed as simply “meat.”

Comey’s book is set to be released on Tuesday. A promo for his interview on ABC — which reportedly lasted five hours, though only one hour of it was aired — was released on Thursday, and less than 24 hours later, Trump jumped on Twitter to call the former FBI director an “untruthful slime-ball.”

There has been speculation of a possible impeachment for Trump as special counsel Robert Mueller continues his investigation into Russian meddling in the 2016 election. Trump has criticized the probe as a “witch hunt” and has wavered in his decision to sit down with Mueller for an interview. Many also believe Trump may fire Mueller or other people associated with the investigation, like Deputy Attorney General Rod RosensteinOver the weekend, it was reported that Mueller may delay issuing the president an obstruction of justice report in order to focus on the Russian collusion probe.

Comey, however, said impeachment is not the best solution, because it would simply “let the American people off the hook.” Instead, he said, the nation is “duty bound” to vote Trump out of office in 2020.

“You cannot have, as president of the United States, someone who does not reflect the values that I believe Republicans treasure and Democrats treasure and independents treasure,” Mr. Comey said. “That is the core of this country. That’s our foundation. And so impeachment, in a way, would short-circuit that.”

In a series of tweets on Sunday morning, Trump called Comey “the worst FBI Director in history,” and claimed his new book left several questions unanswered, including why Comey “lied” to Congress.

Despite his sharp criticism of Trump, Comey also said he does not believe the president is mentally unstable. Instead, he said Trump appears to be someone with “above average intelligence.”

Comey also stated in Sunday’s interview that it was “very weird” for him to discus the infamous “Steele dossier” with Trump just days before his inauguration.

The dossier included allegations that the Russian government possesses video recordings of Trump watching prostitutes urinate on each other in a hotel room in Moscow in 2013. Trump has denied the existence of this “pee tape,” and claims he would never engage in this type of behavior because he’s “a germophobe.”

Perhaps one of Comey’s most audacious comments about Trump was his comparison of the president to a “mob boss.” Comey claimed the president demanded unwavering loyalty from him, another thing Trump denied on Twitter.

Trump also excoriated the former FBI director for his handling of the case involving Hillary Clinton’s emails, and claimed he believed Comey was assuming Clinton would win the 2016 election. Comey re-opened the probe into the former Secretary of State’s private email server about two weeks before the election, months after finding insufficient evidence to incriminate her.