"My judgement was, I needed to get that out in the public square, so I asked a friend of mine to share the content of the memo with a reporter… because I thought that might prompt the appointment of a special counsel," Comey said.
Comey also explained why he recorded his private talks with the US president, saying that he was afraid Trump might "lie" about them.
On Sunday, Trump questioned whether Comey's leaks were "totally illegal" and slammed the ex-FBI chief over acting "cowardly."
"I believe the James Comey leaks will be far more prevalent than anyone ever thought possible. Totally illegal? Very 'cowardly!'" Trump wrote on Twitter.
I believe the James Comey leaks will be far more prevalent than anyone ever thought possible. Totally illegal? Very 'cowardly!'— Donald J. Trump (@realDonaldTrump) 11 июня 2017 г.
The next day after Comey's testimony, Trump also commented it on via Twitter.
"Despite so many false statements and lies, total and complete vindication…and WOW, Comey is a leaker!" Trump wrote.
Following the revelation, Trump's lawyer Marc Kasowitz called for finding out whether by leaking sensitive information the ex-FBI head violated the law.
Trump has repeatedly said that leaks threaten the US national security and called for finding those who share classified information with the press.