Billionaire Elon Musk sparked fevered speculation when he turned up with a black eye for his Oval Office farewell with US President Donald Trump on Friday.

Musk seemingly ended his months-long White House slumber party with a strange and muted send-off.

Musk explains his black eye, says he told son X to punch him Elon Musk attributed his bruised appearance at a White House news conference to his son. “I said, ‘Go ahead, punch me in the face ...

Trump marked the end of Musk's tenure as a government employee with an Oval Office event. Musk arrived with a literal and reputational black eye.

The tech billionaire stood in the Oval Office for more than 30 minutes with a visible black eye before a reporter could ask him about it.