Donald Trump confirms he is being investigated for obstruction of justice

Mr Trump has described the investigation as a 'witch hunt' (Getty)

Donald Trump has said that he is being investigated for possible obstruction of justice over his decision to fire the FBI Director who was heading a probe into possible collusion between his election campaign and Russia's alleged effort to interfere with the 2016 election.

Earlier this week, it was reported that in the aftermath of the firing of James Comey, Robert Mueller, the man appointed to take over the probe as special investigator, had began looking at whether Mr Trump's behaviour represented an obstruction of justice. Mr Mueller has reportedly already scheduled interviews with several senior intelligence officials. Mr Trump's lawyer denounced the development and accused the FBI of leaking material.

Now, Mr Trump has suggested that he is indeed being investigated. "I am being investigated for firing the FBI Director by the man who told me to fire the FBI Director! Witch Hunt," he wrote on Twitter.

It is believed he was referring to Deputy Attorney General Rod Rosenstein, who appointed Mr Mueller as special prosecutor to investigate the Trump campaign. In the immediate aftermath of Mr Comey’s firing, the White House made public, memos from Mr Rosenstein and Attorney General Jeff Sessions that made a case for getting rid the FBI Director. There has certainly been no indication that Mr Mueller told Mr Trump to fire Mr Comey.

The President's words of apparent confirmation come after a week of reports from Washington that his firing of Mr Comey, who was heading up a probe into his former National Security Adviser Michael Flynn and his possible ties to the Kremlin, had led the investigation to broaden its scope.

In another tweet earlier on Friday, Mr Trump had said: “After 7 months of investigations & committee hearings about my 'collusion with the Russians,' nobody has been able to show any proof. Sad!”

The Associated Press said Mr Mueller was among the candidates Mr Trump interviewed to replace Mr Comey. A day later, Mr Rosenstein appointed Mr Mueller, who was at the helm of the FBI during the September 11 attacks, as special counsel.

The tweets are the latest in a week of angry social media responses by the President over a report by the Washington Post that Mr Mueller was looking into whether he had obstructed justice.

The Twitter storm comes as it emerged Vice President Mike Pence had also hired a personal lawyer to represent him in the intensifying investigation. Mr Pence’s office confirmed he had retained Richard Cullen, a former Virginia attorney general and US attorney for the Eastern District of Virginia, to assist “in responding to inquiries” from Mr Mueller.

Mr Mueller's investigation appeared to be reaching a broadening circle of current and former officials. The Post said investigators had requested interviews with CIA Director Dan Coats, National Security Agency chief Michael Rogers and Richard Ledgett, the former NSA deputy director. Recent news reports have suggested Trump sought all three officials' help in pressuring FBI Director James Comey to drop his investigation into Mr Flynn.