Former CIA Director John Brennan says he believes President Donald Trump's campaign colluded with the Russians and that the president revoked his security clearance to "silence others who might dare to challenge him," NY Times reported.

"Mr. Trump’s claims of no collusion are, in a word, hogwash," Brennan noted. He said the only question now is whether the collusion that took place "constituted criminally liable conspiracy."

"Mr. Trump clearly has become more desperate to protect himself and those close to him, which is why he made the politically motivated decision to revoke my security clearance in an attempt to scare into silence others who might dare to challenge him," he noted.