Some federal agencies, including the State and Defense Departments, told their employees not to respond to an email asking for a list of tasks they completed.

Musk is "an employee of the White House Office" and "holds a position as a non-career Special Government Employee," the filing said. "Like other senior White House advisors, Mr Musk has no actual or formal authority to make government decisions himself."

Tech billionaire Elon Musk said Saturday that all federal employees are expected to fill out a mandatory productivity report form and will be considered resigned if they do not.