President Donald Trump has unleashed criticism against James Comey over the former FBI director's forthcoming book.
Trump fired off a series of tweets ahead of Comey's interview with ABC, which is set to air in full Sunday evening (US time).
In an excerpt shown Saturday, Comey said his belief that Hillary Clinton would win the 2016 presidential election was a factor in his decision to disclose the investigation into her e-mails.
Trump seized on that, saying Comey "was making decisions based on the fact that he thought she was going to win, and he wanted a job. Slimeball!"
White House spokeswoman Sarah Huckabee Sanders said Sunday on ABC's "This Week" repeated the president's claim.
"Give me a break, the guy (Comey) knew exactly what he was doing. He thought Hillary Clinton would win and he thought that this would give him some cover," she said.
Comey's disclosure shortly before the 2016 election that the FBI had reopened its investigation into her e-mail use enraged Democrats.
Following Clinton's loss, Democrats blamed Comey and Clinton herself has said it hurt her election prospects.
Trump also suggested Comey should be imprisoned, saying "how come he gave up Classified Information (jail), why did he lie to Congress (jail)." There is no indication Comey is under investigation for doing either.
Asked if the president wanted the Justice Department to investigate Comey, Sanders said that she was not aware of a specific request, but "if they feel there was any wrongdoing, they should certainly look into that just as they do on a number of other topics."
The leading Democrat on the House Intelligence Committee California Congressman Adam Schiff said he always found Comey credible and truthful, but he added that Comey did make "a very serious" mistake in publicly discussing the investigation into Hillary Clinton's e-mail server in the run up to the 2016 presidential election.