In a statement Trump released, he accused Bannon of having "lost his mind" and of being "only in it for himself."

“Steve was rarely in a one-on-one meeting with me and only pretends to have had influence to fool a few people with no access and no clue, whom he helped write phony books,” Trump said.

Allies of Bannon also sought to distance themselves as the extent of his break with Trump became clear.

President Trump Donald John TrumpHR McMaster says president's policy to withdraw troops from Afghanistan is 'unwise' Cast of 'Parks and Rec' reunite for virtual town hall to address Wisconsin voters Biden says Trump should step down over coronavirus response MORE's lawyers on Wednesday also reportedly sent a cease-and-desist letter to Bannon, ordering him to refrain from making "disparaging" statements about Trump and his family.

The Trump administration is also going to start barring White House employees and guests from using their personal cellphones at work, press secretary Sarah Huckabee Sanders said early Thursday.

Sanders said in a statement that the "security and integrity of the technology systems at the White House is a top priority for the Trump administration."

Trump has often talked about leaks of information since he assumed office.

A report surfaced in November that the White House was weighing the ban.