Fighter A will face Fighter B in the co-main event, and Fighter C will now fight in a light heavyweight bout after Fighter D, who was slated to fight in the co-main event, was ruled out due to injury.

According to White, the sellout event was on pace to set a UFC record with a live gate of more than $20 million.

UFC has not announced whether the non-title welterweight bout between McGregor and Chandler will be rescheduled.

Chandler appeared to take the announcement in stride, acknowledging the uncertainty and 'risk' of facing McGregor in a social media post on Friday.

McGregor, 35, was set to return to competition for the first time since he suffered a broken leg in a TKO loss to Dustin Poirier in July 2021.

The former featherweight and lightweight champion has fought only four times since a blockbuster boxing match against Floyd Mayweather Jr.

in 2017.

He is 1-3 in those appearances, with two losses to Poirier and a submission defeat to Khabib Nurmagomedov in a 2018 title fight.

The June fight being called off is a disappointing chapter in what has become something of a saga between McGregor and Chandler, a former champion in Bellator MMA, who first called out McGregor in earnest in 2022.

UFC announced the two would coach against each other on 'The Ultimate Fighter' reality series in early 2023, which went ahead as scheduled that spring.

A fight date did not come together until early this year, however, for various reasons.

UFC's former drug testing partner, the United States Anti-Doping Agency, claimed McGregor's situation led to the dissolution of its UFC program, as the promotion wanted to grant McGregor an exemption of a six-month testing requirement following his leg injury.

UFC chief business officer Hunter Campbell denied that assertion and demanded a public apology.

McGregor, of Ireland, promised in a social media post that his return to the Octagon this year would be the start of the 'Greatest Comeback in Sports History.

' UFC scheduled a news conference with McGregor and Chandler on June 3 at 3Arena in Dublin but canceled the event just 12 hours before doors were to open, which prompted speculation on the status of the fight.

Chandler, 38, has not fought since a back-and-forth loss to Poirier at UFC 281 in November 2022.

He has expressed a passing interest in potential bouts against Fighter E, who is currently not signed to UFC, or BMF titleholder Fighter F.