Mark Zuckerberg is tired of waiting around for his cage match with Elon Musk.

Less than two months after eagerly taking up the Tesla executive's challenge, Zuckerberg has called off the bout. The martial arts-loving Facebook co-founder on Sunday accused Musk of not being serious about the challenge and said "it's time to move on."

"I offered a real date. [UFC president] Dana White offered to make this a legit competition for charity," Zuckerberg posted on Threads, the Twitter rival whose creation started the beef in the first place.

"Elon won't confirm a date, then says he needs surgery, and now asks to do a practice round in my backyard instead," he continued. "If Elon ever gets serious about a real date and official event, he knows how to reach me."

Zuckerberg's post came two days after Musk posted on X, formerly known as Twitter, that the proposed fight would take place in "an epic location" in Italy. He wrote that it would be livestreamed on both X and Meta, and that "everything in camera frame will be ancient Rome, so nothing modern at all."

"Everything done will pay respect to the past and present of Italy," he wrote Friday, before adding that "all proceeds go to veterans" and "pediatric hospitals in Italy."

Last week, the 52-year-old Musk said he would be getting an MRI on his neck and upper back to determine if he needed surgery. Musk had recently posted a video of himself in X headquarters carrying a 45-pound dumbbell.

In a purported private text exchange shared by the journalist Walt Mossberg and later by Musk on Sunday, Musk texted Zuckerberg about "a practice bout at your house," adding that he had "not been practicing much."

Zuckerberg declined the offer, telling Musk to train on his own and let him know when he is ready to compete in "a real MMA fight."

"I don't want to keep hyping something that will never happen, so you should either decide you're going to do this and do it soon, or we should move on," Zuckerberg said.

Representatives for Meta and X did not respond to CNBC Make It's request for comment.

Since Zuckerberg's post, Musk has replied to multiple X posts implying that Zuckerberg is scared to get in the ring with him.

"Zuck is a chicken," he posted Sunday.

Dan Ives, an analyst at Wedbush Securities who has followed Musk and Zuckerberg for years, believes that a fight between the two billionaires is not yet out of the question.

"This is a beat that's not going away," he tells CNBC Make It. "I think it's complex logistics. Musk doesn't want Zuckerberg to have the upper hand in the when, where and how this fight happens."

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