Elon Musk and Mark Zuckerberg are "absolutely dead serious" about trading blows in the Octagon, and fans will have to pay up if they want to watch.

UFC president Dana White on Thursday told TMZ Sports that he spoke with both billionaires about their social media beef this week, which saw Zuckerberg accept a "cage match" challenge issued by Musk on Twitter.

"Mark Zuckerberg hit me up first and said 'is he serious?'" White told the outlet. When the promoter reached out to Musk, the Tesla CEO told him: "Yeah, I'm dead serious."

White said that he is already in "early stages" of planning how to put on the fight, but didn't hesitate to play up the excitement he expects the brawl will create.

"This would be the biggest fight ever in the history of the world, bigger than anything that's ever been done," he said. "It would break all pay-per-view records."

The tech executives have a history of bad blood, with the fight challenge coming after reports emerged that Zuckerberg's Meta is working on building a rival to Twitter.

While a standard UFC pay-per-view costs $80, White said he would charge $100 for the Musk-Zuckerberg bout.

The previous biggest pay-per-view ever was Conor McGregor-Floyd Mayweather in 2017, White said, which brought in more than $600 million in revenue.

Mayweather reportedly took home $275 million after winning, while McGregor walked away with $85 million.

But a fight between Musk and Zuckerberg — the No. 1 and No. 10 richest men on earth with a combined net worth of $340 billion — would easily set a new record, White said.

"I think it triples [Mayweather-McGregor]," he said. "There's no limit on what this thing can make."

The pair likely aren't looking to add to their net worth from the fight, however. Instead, White suggested they would each battle for a charitable organization of their choice.

"I don't think either one of them needs the money," White said. "These guys would raise hundreds of millions of dollars for charity," he added.

White declined to speculate about when the fight might take place, but said he's ready to make it happen.

"If these guys are serious, I make fights that people want to see," he said. "That's what I do for a living."

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