Staffers of the U.S. Agency for International Development were instructed to stay out of the agency’s Washington headquarters on Monday, according to a notice distributed to them, after billionaire Elon Musk announced President Donald Trump had agreed with him to shut the agency.

The agency is the world's biggest donor, dispensing billions in humanitarian aid and development funding annually.

Elon Musk called USAID a criminal organization that should “die.” Proponents say it’s a key arm of U.S. influence that, if destroyed, “cannot be easily rebuilt.”