He also referred to "so many false statements and lies" after Mr Comey bluntly accused the White House of spreading "lies, plain and simple".
The former FBI director, who was fired last month, used his testimony to say he had "no doubt" Mr Trump had fired him because of his department's investigation into Russian meddling in the 2016 US election.
“I take the President at his word that I was fired because of the Russia investigation,” Mr Comey told the Senate Intelligence Committee in a public hearing. “Something about the way I was conducting it, the President felt, created pressure on him he wanted to relieve.”
He added: “I was fired in some way to change…the way the Russian investigation was being conducted. That is a very big deal.”
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