"Mr. President, the American people will hear my story very soon. And they can judge for themselves who is honorable and who is not," Comey said on Twitter.
Comey's pointedly titled book is to be released on April 17, and he has scheduled a number of interviews on it after nearly a year of silence about his firing.
Trump sacked Comey last May in frustration over the Federal Bureau of Investigation's probe into Russian interference in the 2016 election. Comey later released memos he wrote that suggested Trump had pressured him to halt the probe.
Book pre-sales appeared to get a boost when the Justice Department sacked FBI deputy director Andrew McCabe on Friday.
McCabe, who was Comey's deputy and defended him after Trump fired him, was accused by the Justice Department of lying in an internal investigation, and of an unauthorized leak to the media.
But Trump quickly turned McCabe's firing into a political event in tweets over the weekend.
"Andrew McCabe FIRED, a great day for the hard working men and women of the FBI - A great day for Democracy," Trump tweeted.
"Sanctimonious James Comey was his boss and made McCabe look like a choirboy. He knew all about the lies and corruption going on at the highest levels of the FBI!"
"Spent very little time with Andrew McCabe, but he never took notes when he was with me," Trump continued. "I don't believe he made memos except to help his own agenda, probably at a later date. Same with lying James Comey.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)
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