Yet the president unleashed yet another attack on Mr Sessions on Tuesday, telling the Wall Street Journal he was "very disappointed" with Mr Sessions and refusing to rule out firing him.

“It’s not like a great loyal thing about the endorsement,” he said. “I’m very disappointed in Jeff Sessions.”

Asked whether he would remove Mr Sessions from office, Mr Trump repeated that he was disappointed in the attorney general’s decision to recuse himself.

“I’m just looking at it,” he said. “I’ll just see. It’s a very important thing.”

He had begun his attacks at dawn, tweeting shortly after 6am: “Attorney general Jeff Sessions has taken a VERY weak position on Hillary Clinton crimes (where are the e-mails and DNC server) and intel leakers!”