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

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

Trump has already moved to drastically shrink the US federal workforce after mass layoffs shortly following his inauguration in January.

The president’s DOGE, led by Musk, has been prioritising cutting waste across the federal government workforce.

Trump took to his own platform Truth Social to praise Musk over his work to audit the government and encouraged him to “get more aggressive”.

“Remember, we have a country to save,” Trump wrote.

Trump last week signed an executive order for agencies to work with DOGE to “make preparations to initiate large-scale reductions in force”.

However the legality of whether the US president can fire federal employees remains complex.

Most public service employees in the US can only be fired legally for bad performance or misconduct, Reuters reported.

There is also a process and appeal rights if workers are let go.

Trump’s Office of Personnel Management sent out an email to federal employees with the subject line ‘Fork in the Road’, which offered a deferred resignation.

Over 77,000 workers accepted this offer, which cut the government workforce by around 3 per cent in one fell swoop, the White House said.