Elon Musk has told hundreds of thousands of US government workers to explain what they accomplished over the past week or be forced to leave their jobs.

The billionaire, who serves as President Donald Trump’s cost-cutting chief, teased the extraordinary request on his social media network on Saturday, sparking confusion across key agencies.

“Consistent with President @realDonaldTrump’s instructions, all federal employees will shortly receive an email requesting to understand what they got done last week,” Mr Musk posted on X, which he owns.

“Failure to respond will be taken as a resignation.”

Shortly afterward, federal employees received a three-line email with the subject ‘What did you do last week?’ and this instruction: “Please reply to this email with approx. 5 bullets of what you accomplished last week and cc your manager.”

The deadline to reply is Monday at 11.59pm, although the email did not include Mr Musk’s social media threat about those who fail to respond.

The latest unusual directive from Mr Musk’s team – a tactic he used at Twitter – injects a new sense of chaos across beleaguered multiple agencies, including the National Weather Service and the State Department.

Senior officials were on Saturday night working to verify the message’s authenticity and, in some cases, instructed their employees not to respond.

Thousands of government employees have already been forced out of the federal workforce — either by being fired or offered a buyout — during the first month of Trump’s administration as the White House and Mr Musk’s so-called Department of Government Efficiency fire both new and career workers, tell agency leaders to plan for “large-scale reductions in force” and freeze trillions of dollars in federal grant funds.

There is no official figure available for the total firings or lay-offs so far, but it is understood that hundreds of thousands of workers may be affected. Many work outside of Washington, DC.