Donald Trump ordered the firing of special counsel Robert Mueller last June over petty reasons, but backed off when his White House counsel threatened to resign.

The report first appeared in the New York Times, which cited two sources, and was subsequently confirmed by other news agencies.  Robert Mueller is leading an investigation into whether Trump and his campaign colluded with Russian interference in the 2016 presidential election.

The account states that Trump was angry with Mueller not just for the investigation, but because:  Mueller resigned from Trump National Golf Club in Sterling, Virginia in a dispute over fees; that Mueller could not be impartial because he had most recently worked for the law firm that had previously represented the president's son-in-law, Jared Kushner; and because Mueller had been interviewed to return as the FBI director the day before he was appointed special counsel in May.

White House Special Counsel Don McGahn refused to go along with Trump's order, telling senior White House officials that dismissing Mueller would have disastrous effects on Trump's presidency (not to mention the rule of law, I guess).  McGahn told them he'd rather resign, and Trump backed down.

Trump's lawyers declined to comment "out of respect for the Office of the Special Counsel and its process".

The vice chairman of the Senate Intelligence Committee, Virginia Senator Mark Warner, said that sacking the special counsel "is a red line that the President cannot cross".

"Any attempt to remove the Special Counsel, pardon key witnesses, or otherwise interfere in the investigation, would be a gross abuse of power, and all members of Congress, from both parties, have a responsibility to our Constitution and to our country to make that clear immediately," Warner said in the statement.