Mike Pompeo, the US Secretary of State, on Sunday publicly warned administration staff that they needed to either work with the Trump agenda or leave their positions.

His comments came after reports that Rod Rosenstein, the deputy attorney general, discussed wearing a wire and recruiting cabinet members to invoke the 25th amendment in the days following the firing of James Comey, the FBI director.

The 25th amendment allows for the removal of the president from office if he or she was deemed unfit to carry out duties.

In a thinly-veiled attack raising further questions over whether Mr Trump would fire Mr Rosenstein, Mr Pompeo suggested that White House officials should find "something else to do" if they do not support President Trump's agenda.

"I’ve been pretty clear since my beginning of service here in this administration, if you can’t be on the team, if you’re not supporting this mission, then maybe you ought to find something else to do,” he said.