U.S. President Donald Trump said Friday he was pushing through a massive overhaul of the civil service system, giving him power to directly hire and fire as many as 50,000 jobs reserved for career federal employees.

The changes, outlined in a proposed rule by the Office of Personnel Management, give size and shape to an executive order Trump signed on his first day back in office. If approved, they would represent the biggest change to laws governing political patronage since 1883.

"Moving forward, career government employees, working on policy matters, will be classified as ‘Schedule Policy/Career,’ and will be held to the highest standards of conduct and performance,” Trump said in a post to his social media network. "If these government workers refuse to advance the policy interests of the President, or are engaging in corrupt behavior, they should no longer have a job.”