President Donald Trump is trying to revoke collective bargaining rights from most federal employees — the latest move in his aggressive campaign to weaken the federal workforce. Trump issued an executive order late Thursday night relying on a rarely used provision of the federal labor laws that authorizes the president to exclude agencies from long-standing unionization rights if he determines that those agencies are primarily engaged in national security work.

An executive order on Thursday aimed to end collective bargaining for workers at numerous departments and agencies.