U.S. President Donald Trump has announced that immigration adviser and loyal partisan firebrand Stephen Miller will take over as White House chief of staff, succeeding Susie Wiles.

Trump revealed the leadership change on his Truth Social account on Friday, describing Miller as one of his most trusted advisers. Wiles, the highest-ranking administration official to exit following the Republican Party's midterm election losses, is moving over to the Trump Political Operation.

Miller, who has served as a close confidant and deputy chief of staff across both of Trump's presidential terms, is widely known as the architect behind the administration's hardline border and mass deportation policies. Speaking to reporters outside the White House, Trump defended the shuffle, stating that he wanted to make a change and noting that Miller has been with him from the beginning.

Political analysts note that elevating Miller signals an aggressive doubling-down on the administration's core agenda and sets the stage for likely political clashes. With Democrats poised to take control of both the U.S. House of Representatives and the Senate in January, lawmakers are widely expected to launch investigations into Miller as he steps into the top staff role on Monday.