WASHINGTON — President Trump’s lawyer, Rudolph W. Giuliani, attacked the credibility of a former White House counsel on Friday, saying his account of how Mr. Trump told him to remove the special counsel was inaccurate.

Mr. Giuliani’s statement was the most extensive pushback by the president’s lawyers against the former counsel, Donald F. McGahn II, who cooperated extensively with the special counsel’s investigators. The report detailing the findings of the investigation, released on Thursday, also included several damning examples of how Mr. Trump tried to interfere with the investigation, like Mr. McGahn’s account.

“It can’t be taken at face value,” Mr. Giuliani said in an interview. “It could be the product of an inaccurate recollection or could be the product of something else.”

Mr. McGahn’s lawyer, William A. Burck, pushed back on Mr. Giuliani’s attack.

“It’s a mystery why Rudy Giuliani feels the need to relitigate incidents the attorney general and deputy attorney general have concluded were not obstruction,” Mr. Burck said. “But they are accurately described in the report.”