DONALD Trump has appeared to confirm he is under investigation for obstruction of justice, claiming he is being probed for firing FBI director James Comey by the man he says told him to do it.

It was not clear whether the US President was basing his tweet on direct knowledge or on this week’s reports special counsel Robert Mueller is examining whether he obstructed justice by firing Comey last month amid the Russia investigation.

Mueller was appointed as special counsel to investigate claims of Moscow involvement in last year’s presidential election and possible collusion by Trump associates with the Russians, but there has been no indication Mueller told the President to fire Comey.

Trump tweeted: “I am being investigated for firing the FBI Director by the man who told me to fire the FBI Director! Witch Hunt.”

In another tweet, he wrote: “After 7 months of investigations & committee hearings about my ‘collusion with the Russians,’ nobody has been able to show any proof. Sad!”

Deputy attorney general Rod Rosenstein submitted a memo to the President last month raising concerns over Comey, but Trump later said he had already made the decision to fire Comey.

The White House confirmed Mueller was among candidates the president interviewed to replace Comey. A day later, Rosenstein appointed Mueller, who was at the helm of the FBI during the 9/11 attacks, as special counsel.

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

In a series of statements on Twitter on Thursday, Trump repeated his claim that Mueller’s investigation is a “witch hunt” based on the “phony” premise of possible collusion between Russia and Trump campaign associates.

The President complained the probe is unfair and wondered why his defeated Democratic opponent was not getting the same scrutiny.

“Why is that Hillary Clintons family and Dems dealings with Russia are not looked at, but my non-dealings are?” he asked.

“They made up a phony collusion with the Russians story, found zero proof, so now they go for obstruction of justice on the phony story. Nice.”