Donald Trump launched a fiery attack on James Comey after the former FBI director indicated that he thinks the president obstructed justice in the Russia investigation.

'James Comey is a disgrace to the FBI & will go down as the worst Director in its long and once proud history,' Trump wrote on Twitter Thursday night.

'He brought the FBI down, almost all Republicans & Democrats thought he should be FIRED, but the FBI will regain greatness because of the great men & women who work there!'

The tweet came just one hour after Comey discussed the report from special counsel Robert Mueller at a CNN town hall moderated by Anderson Cooper.

The former FBI head made it clear that there is no love lost between him and Trump, who fired him two years ago to the day.

Comey described the president as a 'chronic liar' who on more than one occasion displayed a 'corrupt intent to interfere' with the Russia investigation, which he helped launch.

Donald Trump launched a Twitter attack on James Comey after the former FBI director indicated that he thinks the president obstructed justice in the Russia investigation

Former FBI Director James Comey shared his personal conclusions from the Mueller report at a CNN town hall on Thursday. Comey, who was fired by President Donald Trump two years ago to the day, made it clear there is no love lost between him and his old boss

When asked whether he thought that obstruction charges should be brought against Trump when he leaves the White House, Comey said: 'I think the justice department will have to take a serious look at that.

'Whether it's a wise thing to do to a former president, I don't know. That's a harder question, a much bigger question than the facts of the case.'

Cooper pressed: 'But you think the evidence is there to prosecute?'

'Sure looks like it's there with respect to at least a couple of those episodes of obstruction,' Comey replied.

He continued: 'There is a whole lot of facts laid out in Bob Mueller's report that raise serious questions about whether there is a chargeable case for obstruction and witness tampering against this president.'

On the findings of the Mueller report, Comey told Cooper he was not surprised by the outcome.

He said: 'There were a lot of facts in the Mueller report that I didn't know, but I knew it would be high quality work if we got a chance as a country to read it,' Comey said.

'And what he describes about Russia's intervention in our election didn't surprise me at all. It confirmed what I knew from when I was at the bureau.

'And what he laid out about the president's efforts to obstruct justice was broader in scope than I personally knew, but given what I had seen, it didn't surprise me, honestly.'

He said that he felt the parts he was featured in were accurate before Cooper probed whether he felt that the report vindicated him 'because some of the things that President Trump said you were lying about, Mueller backed you up and said that they weren't lies'.

Comey replied: 'I knew I was telling the truth the whole time. I basically told that same story under oath in front of the senate at a time when the president was hinting that there were tapes of our conversations together. So I knew I was telling the truth. I think the country knew I was telling the truth, and Mueller simply confirmed that.'

Trump went after both Comey and Mueller earlier in the day when he told reporters at the white house that the special counsel is 'in love with James Comey. He likes James Comey. They were very good friends, supposedly best friends. Maybe not, but supposedly best friends.

'You look at the picture file and you see hundreds of pictures of him and Comey.'