President Trump tried to use the Russian probe to justify the firing of former FBI director James Comey, a former bureau chief revealed.

Former acting FBI Director Andrew McCabe, who was himself removed by Donald Trump, said the president wanted the Russia investigation linked to Comey's firing in a memo.

As Comey's replacement as director, McCabe said President Trump wanted Deputy Attorney General Rod Rosenstein to highlight the probe into Russian collusion in the 2016 campaign in a letter justifying the firing of Comey.

He added Trump wanted Rosenstein to 'give him cover' to fire Comey by citing the Russia investigation in the memo, which could be construed as an attempt by the president to interfere with the probe.

President Trump wanted the Russia investigation in to links between the Kremlin and his 2016 campaign linked to the firing of FBI director James Comey

Comey's replacement, Andrew McCabe, told 60 Minutes Trump tired to get the Russia probe mentioned in a memo outlining why Comey was fired

But Rosenstein did not want to mention the Russian investigation and told Trump it should be excluded, McCabe said.

The final memo outlining why Comey should be fired did not include any mention of the probe.

In an interview with 60 Minutes, McCabe said Rosenstein was concerned about his conversation with the president and did not want to be seen to be obstructing the Russia investigation.

'He explained to the president that he did not need Russia in his memo. And the president responded, "I understand that, I am asking you to put Russia in the memo anyway".

'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.'

Despite the Russia probe not being mentioned in the memo, Trump still used it as a justification in an interview with NBC News in May 2017, just after the firing of Comey.

Former FBI director James Comey was fired in May 2017. He is pictured here being sworn in while testifying before the Senate Intelligence Committee two months later

He then repeated this assertion in an Oval Office meeting with top Russian officials.

McCabe added: '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, who became acting director after Comey’s firing, said he was disturbed by his conversation with Trump following Comey’s dismissal and got the investigations started the following day.

He said he began an obstruction of justice and counterintelligence investigation involving Trump and his ties to Russia after Trump fired bureau director Comey.

McCabe also said in the interview that Trump told his top intelligence officials that he believed Russian President Vladimir Putin more than he did FBI investigators.

Russian President Vladimir Putin and U.S. President Donald Trump shaking hands ahead of their bilateral summit in Helsinki, Finland, in July last year

The former FBI director said that he was told by an FBI official that Trump was convinced by Putin that North Korea was incapable of hitting the United States with ballistic missiles - even though American spy agencies claimed otherwise.

In the first public confirmation of the investigation by an official who was involved, McCabe described events that occurred in the eight days between Comey’s firing and the appointment of Special Counsel Robert Mueller to take over the investigations of Russian interference in the 2016 U.S. election.

McCabe also told how he had a 'bizarre' interview for the position of FBI director, in which Trump said '80 per cent of FBI employees must have voted for him' and asked if he thought that was true.

Trump tore into McCabe on Twitter on Thursday morning after the former law enforcement official lifted the lid on conversations to oust the sitting president.

He used McCabe's wife Jill's failed candidacy for office in Virginia, where she ran for office as a Democrat with the financial backing of an organization that is close to Hillary Clinton.

The president suggested the connection to the former secretary of state who opposed him for the Oval Office caused McCabe to go easy on Clinton in the FBI's probe into her use of a private email and server.

During the 60 Minutes interview yesterday, McCabe said revealed Rosenstein was discussing invoking the Constitution's 25th Amendment, which allows Cabinet members to seek the removal of a president if they conclude that he or she is mentally unfit.