Fans gathered to watch the extravaganza on a giant screen on the Ellipse outside the White House, defending the event.
Trump, who has deep ties with the sport, has defended the UFC event as a unique spectacle.
“This is going to be an event you’re really gonna like,” Trump said as he hosted some of the fighters in the Oval Office in May.
The White House says the UFC is bearing the entire cost.
Sponsors, including Bud Light and Polymarket, had their logos emblazoned on the Octagon, with the broadcast handled exclusively by Paramount.
For his last birthday, Trump oversaw a military parade in Washington, marking the 250th anniversary of the US Army.
