U.S. President Donald Trump will have more power to hire and fire up to 50,000 career federal employees in an overhaul of the government’s civil service system announced by his administration on Thursday.

The overhaul, released by the Office of Personnel Management, fulfills Trump’s campaign pledge to strip job protections from federal workers deemed by the president’s team to be “influencing” government policy.

It is the biggest change to the rules governing the civil service in more than a century and targets employees that the administration sees as undermining the president’s priorities. Trump called the overhaul “Schedule F” during his first administration.

“You can’t run an organization if people are refusing to actually carry out the lawful objectives and orders of the administration,” said OPM Director Scott Kupor, the administration’s top HR official.