Former Attorney General Alberto Gonzales criticized former FBI Director James Comey on Friday for failing to notify his superiors at the Justice Department of concerns with his conversations with President Trump.

"If in fact Jim Comey felt so strongly about the pressure he was feeling from the White House, he had an obligation in my judgment … to notify Jeff Sessions, Rod Rosenstein, Dana Boente, someone, because it is the job of the attorney general and the deputy attorney general to protect all the bureaus and services and divisions within the Department of Justice," Gonzales said on CNN's "New Day."

Gonzales said that had Comey notified his superiors, someone like Sessions could've warned Trump that his conversations with Comey were improper and "dangerous."

But if Comey didn't speak with top Justice Department officials, Gonzales said he "failed at his job."

"I really have a serious issue, if in fact Jim Comey did not notify his superior, that is his job," he said. "That is the best thing he can do to protect the bureau."

Details of Comey's reservations about his interactions with Trump were detailed by Benjamin Wittes, a friend of the former FBI director and senior fellow at the Brookings Institute.

Wittes recalled various conversations he had with Comey in an interview with the New York Times and on the Lawfare blog, of which he is editor-in-chief.

Comey also detailed his conversations with Trump in memos, including one where Trump allegedly asked the former FBI director to end the bureau's investigation into former national security adviser Mike Flynn.

Gonzales served as President George W. Bush's attorney general from 2005 to 2007, and has a rocky history with Comey.

The two sparred over the legality of a National Security Agency domestic surveillance program, and had a famous showdown in a Washington, D.C., hospital beside former Attorney General John Ashcroft's bed.

Gonzales was White House counsel at the time, and Comey was serving as acting attorney general.