On the day before President Trump fired FBI Director James B. Comey, he summoned his vice president, chief of staff, top lawyer and other senior advisers to the Oval Office.

He was ready to get rid of Comey, Trump told them that Monday morning in May, and had prepared a termination letter that laid out in detail his many frustrations, which had boiled over the previous weekend at his private golf club in Bedminster, N.J.

The multi-page letter blasted Comey over his investigation of Trump’s Democratic presidential opponent, Hillary Clinton. And, according to a person with direct knowledge of the contents of the letter, it conveyed Trump’s displeasure that Comey would not say publicly what he had told the president three times privately: that the FBI’s probe into Russia’s interference in the 2016 election was not focused on him.