Musk warned federal employees over the weekend that non-responses to the email would "be taken as a resignation."

U.S. Treasury employees may need to respond now to Musk’s email, but leaders at other agencies have told their workers to ignore it altogether, according to CNN. Decisionmakers at the Pentagon, the Department of Homeland Security, the Department of Energy, and the Department of Justice have told employees to just not respond to Musk’s demands.

The Office of Personnel Management told workers replying to billionaire Elon Musk's questions about their job accomplishments was 'voluntary.'