Sanders spoke after NBC News reported that Kelly called Trump an "idiot" who does not understand policy issues, comments that the top aide denied making.

"Both the president and the chief of staff are very happy with the position he holds, which is chief of staff to the president," Sanders told reporters. ADVERTISEMENT The spokesperson also knocked down reports that the president might nominate Kelly to lead the Department of Veterans Affairs (VA).

“No, he is not being considered as the VA secretary," Sanders said.

Trump's previous VA nominee, Ronny Jackson, withdrew his nomination amid allegations he drank on the job, presided over a toxic work environment at the White House Medical Unit and overprescribed medication.

Sanders is seeking to quell renewed speculation about Kelly's future in the White House.

The retired Marine Corps general has been losing clout as Trump has tired of his efforts to impose order in the West Wing.

Trump took to Twitter on Monday night to deny tensions between him and his staff.

"The White House is running very smoothly despite phony Witch Hunts etc. There is great Energy and unending Stamina, both necessary to get things done. We are accomplishing the unthinkable and setting positive records while doing so! Fake News is going 'bonkers!'” he wrote.

Kelly released a statement shortly after the NBC News report was published, calling it "total BS."