US President Donald Trump last June ordered Special Counsel Robert Mueller fired but backed down after the White House counsel threatened to resign rather than follow his directive, The New York Times reported on Friday (NZ time).
The Times cited four people told of the matter but there were no immediate responses to requests for comment from White House lawyers and press officials.
Mr Mueller, who is investigating allegations of Russian meddling in the 2016 US election, learned of the incident in recent months as his investigators interviewed current and former senior White House officials in an inquiry into whether the president obstructed justice, the Times reported.
Amid media reports that Mr Mueller was looking into a possible obstruction case, Mr Trump argued that the former FBI director had three conflicts of interest that disqualified him from overseeing the probe, two of the people said, according to the Times.
First, Mr Trump said that a dispute years ago over fees at Trump National Golf Club in Sterling, Virginia, had led Mr Mueller to resign his membership, the newspaper reported.
The President also said Mr Mueller could not be impartial because he had most recently worked for a law firm that previously represented the President's son-in-law, Jared Kushner.
Mr Trump also said Mr Mueller had been interviewed to return as the director of the Federal Bureau of Investigation the day before he was appointed special counsel in May, the Times reported, citing the two people.
White House counsel Donald McGahn said he would quit rather than follow through on the order to fire Mr Mueller, the Times reported.
Mr Trump later said the report was "fake news".
"Fake news, folks, fake news," Mr Trump told reporters in Davos, when asked about the report.