"I started to worry that other people would have the same reaction I do and we'd all be shrugging at the president of the United States saying that private citizens should be in jail," Comey said regarding Trump calling for the former FBI director he fired to be prosecuted. "That's not normal. That's not OK."
In recent days, Trump has directed a series of tweets at Comey, with one tweet calling him a "proven leaker and liar."
James Comey is a proven LEAKER & LIAR. Virtually everyone in Washington thought he should be fired for the terrible job he did-until he was, in fact, fired. He leaked CLASSIFIED information, for which he should be prosecuted. He lied to Congress under OATH. He is a weak and.....— Donald J. Trump (@realDonaldTrump) April 13, 2018
The president and his allies of the Republican National Committee have been on the attack the last few days, insisting that Comey broke FBI protocol when he was director, that he was politically motivated and is lying about his private meetings with Trump.
Comey pushed back on those accusations during the interview, saying the FBI has acted appropriately and that personal feelings did not impact the Russia investigation.
MORE: Comey recalls Trump's reaction to dossier
During the interview, Comey also recalled the moment he first learned of his firing last May. He was in Los Angeles at the time and saw television screens announcing he had resigned and then corrected to him being fired.
"It was disorienting actually, and it was hard to believe and I felt a little bit sick to my stomach frankly," he said.
Comey is on a media tour talking to various outlets promoting his book, "A Higher Loyalty: Truth, Lies, and Leadership," which was released Tuesday.
Tuesday's interview was right after his "Good Morning America" appearance, his first live interview of his tour, during which he said it was not acceptable for the president to call for the imprisonment of private citizens.
He said he worries people will become "numb" to Trump's remarks and tweets.
In his Sunday interview on ABC's 20/20, Comey declared Trump to be "morally unfit to be president," saying the president constantly lies and also criticized him for treating women like "pieces of meat."
FULL TRANSCRIPT: James Comey's interview with ABC News chief anchor George Stephanopoulos