Acting FBI head Andrew McCabe would not confirm whether recently fired FBI Director James Comey had told President Donald Trump that he was not under investigation.

Mr Trump told Mr Comey in a letter, “While I greatly appreciate you informing me, on three separate occasions, that I am not under investigation, I nevertheless concur with the judgment of the Department of Justice that you are not able to effectively lead the Bureau.”

Based on documents released by the White House, Mr Trump fired Mr Comey over the way he handled an investigation into Hillary Clinton’s use of a private email server while she was Secretary of State.

Mr Comey was also the head of an ongoing probe into Russian meddling in the US 2016 presidential election and alleged ties between Moscow and Trump associates.

During a Senate hearing, Republican Senator Andrew Burr asked Mr McCabe if he ever heard Mr Comey tell the president he wasn't the subject of an investigation. McCabe said he “can't comment on any conversations the director may have had with the president.”

But Mr McCabe did vow to tell the Senate Intelligence Committee if the White House tried to interfere with the bureau’s Russia probe — though he asserted that there had “been no effort to impede our investigation to date.”