James Comey's book "A Higher Loyalty" won't be available to purchase until Tuesday, but it's already a bestseller. In the interview, Comey said that Trump was "morally unfit" to be President of the United States but did not call for impeachment.
"Do you think the Russians have something on Donald Trump?".
"These are more words I never thought I'd utter about a president of the United States, but it's possible", Comey told ABC News' chief anchor George Stephanopoulos. "I wish I wasn't saying it, but it's the truth".
"I think it's possible".
Former FBI Director James Comey will break his silence Sunday night in an exclusive interview with ABC News.
Comey is "weak", and was a "terrible director", Trump said.
He also compares the President to one of the ego-driven mafia bosses he took on when he worked as a lawyer. The retired general pleaded guilty in December and is now cooperating with Mueller's investigation.
When asked by Stephanopoulos is he believes that Rosenstein would carry out such an order, Comey said that he may not in an effort to make up for Comey's firing. Comey responded, "Possibly. It's certainly some evidence of obstruction of justice".
Comey interpreted it as a directive to drop the criminal investigation of Michael Flynn, who had just been forced out from his post as National Security Adviser the day before.
Yet Comey said he hopes Trump will not be impeached and removed from office.
In his book, Comey deferred to the Mueller investigation on the question of obstruction. "I think he's morally unfit to be president", Mr Comey replied.
Macmillan, the publishing house behind the book, has ordered an initial print run of 850,000 copies, expecting super-charged sales.
GEORGE STEPHANOPOULOS: You write that President Trump is unethical, untethered to the truth.
The President and his allies have launched a forceful counterattack. But he did not watch the entire program, the White House press secretary, Sarah Sanders, said.
Still, he says it strikes him as unlikely but something that he can't say without high confidence.
Clinton has discussed Comey's decision to announce a reopening of the email probe so close to the election in her own book What Happened and also stated at an event reported by CNN that: "He dumped that on me on October 28, and I immediately start falling".
"I did not go into the business about people peeing on each other", he said.
Last summer, Senate Judiciary Chairman Chuck Grassley and Sen. Disgruntled, he, McCabe, and the others, committed many crimes!'
Some also felt Comey brazenly admitted to illegal acts in the interview, which should be prosecuted.
Trump has denied having asked Comey for his loyalty.
Trump and the Republicans have sought to stifle the impact of his book by accusing Comey of leaking classified materials and of corruptly handling the 2016 investigation into Clinton.
Comey didn't limit his criticisms to Republicans, saying that some of President Obama's behavior surrounding the Clinton email scandal baffled him as well. But Trump later said he was thinking about "this Russian Federation thing" around the time he chose to fire Comey.