President Donald Trump's ambitious plan to host a historic UFC fight night on the South Lawn is facing a major star-power crisis just days before the opening bell.

The historic event, named UFC Freedom 250 and scheduled for June 14 to coincide with Trump's 80th birthday, has quickly become the hottest ticket in Washington.

However, behind the scenes, organizers are facing a brutal reality check as Hollywood celebrities and athletes continue to reject invitations to sit ringside.

UFC president Dana White and White House staff have been working overtime to recruit a guest list to match the sheer scale of the $60 million production.

White revealed that he extended personal invitations to a handful of Hollywood icons and sports legends, including Adam Sandler, Tom Brady, Jared Leto, and Dwayne 'The Rock' Johnson.

Yet the promotional push has fallen completely flat, with representatives for Johnson, Sandler, and Leto confirming to Vanity Fair that they will not be attending. Reps for the others stars did not respond.

The celebrity snubs speak to a growing trend in Trump's second term, with stars increasingly hesitant to align themselves with highly partisan administration events.

Meanwhile, a concert series planned for the National Mall as part of America's 250th anniversary celebrations collapsed this week after nearly all acts pulled out.

Performers including a member of Milli Vanilli, Bret Michaels and Flo Rida were on the bill before the withdrawal. Several cited Trump's partisanship as a reason for bailing.

Trump responded by announcing he would replace the concert with a campaign rally, calling the departed artists 'Third Rate' in a series of social media posts.

Even some of Trump's own supporters were unimpressed. Daily Wire host Matt Walsh blasted the handling of America 250 as a bungled mess turned into 'a Trump rally where Trump will talk about himself for 90 minutes.'

Despite the celebrity cold shoulder, the fight night remains the hottest ticket in Washington among the MAGA faithful and those seeking favour with the administration.

Some 4,000 guests will pack around an octagon erected on the South Lawn, with ringside seats reportedly going to those who have stumped up more than $1 million in sponsorship.

Trump controls 1,000 tickets personally, with White and Ari Emanuel holding 200 each. Chief of staff Susie Wiles has been helping the president hand-pick attendees.

TKO Group Holdings president Mark Shapiro put the total cost of the event at around $60 million, with UFC said to be shouldering most of the bill.