Former FBI Deputy Director Andrew McCabe says President Trump pressured Deputy Attorney General Rod Rosenstein into mentioning Russia in the memo the president cited as justification to fire FBI Director James Comey in May 2017.

"Rod was concerned by his interactions with the president, who seemed to be very focused on firing the director and saying things like, 'Make sure you put Russia in your memo.' That concerned Rod in the same way that it concerned me and the FBI investigators on the Russia case," McCabe, who briefly became acting FBI director after Comey's ouster, told "60 Minutes" in an interview that aired on CBS Sunday evening.

"If Deputy Attorney General Rosenstein listed the Russia investigation in his memo to the White House, it could look like he was obstructing the Russia probe by suggesting Comey's firing," he added. "And by implication, it would give the president cover."

Rosenstein did not include Russia in that memo, despite the president's insistence that it be there. The memo instead focused on the "mistakes" Comey made in handling the investigation into former Secretary of State Hillary Clinton's unauthorized email server. But the president made the connection anyway during an interview with NBC a couple days later, saying the “Russia thing” was a factor in firing Comey.

McCabe, who is on a media tour for his upcoming book, attributed this as one of the factors informing his decision to order an obstruction of justice investigation into Trump. A second reason was Trump's private conversation with Comey, described in memos Comey wrote and leaked to the media, in which the president asked his then-FBI director to drop an investigation into former national security adviser Michael Flynn. A third reason McCabe listed was Trump reportedly telling Russian officials visiting the White House that firing "nut job" Comey relieved "great pressure."

"Put together, these circumstances were articulable facts that indicated that a crime may have been committed. The president may have been engaged in obstruction of justice in the firing of Jim Comey," McCabe said, adding later, "So all those same sorts of facts cause us to wonder is there an inappropriate relationship, a connection between this president and our most fearsome enemy, the government of Russia?"

In his memoir due out next week, "The Threat: How the FBI Protects America in the Age of Terror and Trump," McCabe wrote Rosenstein spiraled into rage and paranoia after Trump ordered him to write the memo. Eight days after Comey was fired, Rosenstein appointed special counsel Robert Mueller to lead the federal investigation into Russian interference in the 2016 election.

The account in McCabe's book about Rosenstein echoes reporting by the New York Times that focused on the struggle the deputy attorney general went through in the days after Comey was fired. Although Rosenstein told Congress that same month he “stand[s] by” the controversial memo he wrote, he privately lamented how the ordeal tarnished his reputation. Rosenstein was “shaken,” “unsteady,” and “overwhelmed,” one person who spoke with Rosenstein told the paper. Another source said he was "frantic, nervous, upset and emotionally dis-regulated."

A Justice Department spokeswoman offered a different explanation for why Rosenstein was upset, pinning the blame on McCabe for not informing him of memos Comey wrote outlining conversations he had with Trump. “To be clear, he was upset not because knowledge of the existence of the memos would have changed the [deputy attorney general's] decision regarding Mr. Comey, but that Mr. McCabe chose not to tell him about their existence until only hours before someone shared them with The New York Times,” DOJ's Sarah Isgur Flores told the Times.

McCabe was fired on March 16, 2018, less than two days before he planned to retire on his 50th birthday and collect a full pension, after the Justice Department's Office of the Inspector General determined that he misled investigators about the role he had in leaking information to the Wall Street Journal in October 2016 about the investigation into the Clinton Foundation. In April, it was revealed that the Justice Department IG had referred its findings to the U.S. attorney’s office in Washington for possible criminal charges while McCabe is mulling whether to sue the government to get his pension back.