Comey, speaking to the Senate Intelligence Committee on Thursday morning, had harsh words for the White House throughout questioning from lawmakers, saying repeatedly he was uncomfortable with the president's requests for loyalty and that the administration lied and defamed him after he was unexpectedly fired in May.
Trump, however, disagreed.
His comments echoed remarks made by his lawyer Marc Kasowitz on Thursday.
"It is overwhelmingly clear that there have been and continue to be those in government who are actively attempting to undermine this administration with selective and illegal leaks of classified information and privileged communications," Kasowitz said at a press conference. "Mr. Comey has now admitted that he is one of the leakers."
All eyes were on the former director as he spoke about the FBI's ongoing investigation into Russian meddling in the U.S. presidential election. Shortly after Comey was fired, the Department of Justice appointed former FBI Director Robert Mueller to serve as a special counsel to oversee the investigation, a decision that has reportedly left Trump fuming.
Trump is well-known for his early morning tweetstorms following major news events. He recently unleashed a furious defense of the White House's second attempt at a travel ban aimed at citizens from six Muslim-majority nations.
"That's right, we need a travel ban for certain dangerous countries, not some politically correct term that won't help us protect people!" he wrote.