WASHINGTON, United States (AFP) — US President Donald Trump hosts a grand Oval Office farewell for Elon Musk on Friday as the world’s richest man ends his turbulent reign as the government’s cost cutter-in-chief.

The pair will hold a joint press conference at 1.30pm (1730 GMT), with Trump attempting to put a positive spin on Musk’s departure from the so-called Department of Government Efficiency (DOGE) after just four months.

Trump, 78, praised the “terrific” Musk on Thursday and insisted that his influence would continue despite the South African-born tech tycoon returning to his Space X and Tesla companies.

“This will be his last day, but not really, because he will, always, be with us, helping all the way,” Trump said on his Truth Social network.

Vice President JD Vance praised Musk’s “incredible” job in an interview with Newsmax and vowed that “the DOGE effort will continue.”

But the news conference will be a far cry from Musk’s first dramatic appearance in the Oval Office in February, when he brought his young son with him and outshone even the attention-seeking president himself.

At the time the 53-year-old was almost inseparable from Trump, glued to his side on Air Force One, Marine One, in the White House and at Trump’s Mar-a-Lago resort in Florida.

Yet Musk is now leaving Trump’s administration under a cloud, after openly admitting disillusionment with his role, and criticising the Republican president’s spending plans.

– DOGE rampage –
The right-wing magnate’s DOGE has led an ideologically-driven rampage through the federal government, with its young “tech bros” slashing tens of thousands of jobs.

It has also shuttered whole departments including the US Agency for International Development (USAID), leading to huge cuts in foreign aid that critics say will hit some of the world’s poorest people and boost US rivals.

But DOGE’s achievements fell far short of Musk’s boasts when he blazed into Washington brandishing a chainsaw at a conservative event and bragged that it would be easy to cut two trillion dollars.

Trump also loudly proclaimed that DOGE was cutting “waste” and would regularly reel off long lists of alleged fraud that Musk’s team was discovering, including social security claimants older than the world’s oldest person.

In reality, the independent “Doge Tracker” site has counted just $12 billion in savings so far while the Atlantic magazine put it far lower, at $2 billion.

Musk’s Silicon Valley-style “move fast and break things” mantra was also at odds with some of his Washington colleagues.

He clashed with other cabinet members and said in an interview earlier this week that he was “disappointed” in Trump’s recent mega tax and spending bill as it undermined DOGE’s cuts.

Musk’s companies, meanwhile, were suffering.

Tesla shareholders called for him to return to work as sales slumped and protests targeted the electric vehicle maker, while Space X had a series of fiery rocket failures.

At Friday’s press conference Musk may also face questions over a New York Times report alleging intensive drug use by the tycoon while on the campaign trail for Trump last year.

The Times said the 53-year-old told friends he was taking so much of the anesthetic ketamine “that it was affecting his bladder, a known effect of chronic use.”

Musk has previously admitted to taking ketamine, saying he was prescribed it to treat a “negative frame of mind” and suggesting his use of drugs benefited Tesla investors.