Mark Zuckerberg says Elon Musk 'isn't serious' about cage match and it's 'time to move on'

Meta CEO Mark Zuckerberg said on Sunday that X owner Elon Musk "isn't serious" about a potential cage match, adding that it's "time to move on" from the much-hyped plans.

"If Elon ever gets serious about a real date and official event, he knows how to reach me," Zuckerberg added in a post on the Meta-owned social media network Threads.

Plans for a cage match between the billionaire entrepreneurs appeared to regain momentum one week prior when Zuckerberg said in a Threads post that he had suggested to Musk the date of Aug. 26 for the fight.

A day later, Musk said in a tweet that he may need surgery for his neck and back, adding that the "exact date is still in flux."

Musk previously sent a text message to Zuckerberg requesting a practice fight in the mixed-martial arts training facility at Zuckerberg's home, according to text messages posted on X by Walter Isaacson, the author of a forthcoming book on Musk.

In his Threads post on Sunday, Zuckerberg characterized the actions by Musk as part of an effort to delay a fight or avoid one altogether.

"Elon won't confirm a date, then says he needs surgery, and now asks to do a practice round in my backyard instead," Zuckerberg said.

X, formerly known as Twitter, did not immediately respond to ABC News' request for comment. Meta declined to comment.

On Friday, Musk announced in a post that the fight would be broadcast on X and Meta and arrangements for the event would be organized jointly by foundations affiliated with Musk and Zuckerberg. The event was set to take place in Rome, Italy, Musk added.

"Everything in camera frame will be ancient Rome, so nothing modern at all," Musk said. "Everything done will pay respect to the past and present of Italy."

All proceeds from the event were set to go to charities in support of veterans, Musk said.

Such a competition would not be the first for Zuckerberg. In May, he won two medals in a Brazilian Jiu-Jitsu tournament held at a high school in Silicon Valley.

In the text messages released by Isaacson, however, Musk acknowledged that he had "not been practicing much."

The run-up to a hypothetical fight between the two has played out alongside a real-life competition waged by their near-identical social media platforms: Zuckerberg's newly-launched Threads and Musk's X.

Days after its launch last month, Threads reached 100 million users faster than any app ever created; user engagement, however, has fallen dramatically since the initial burst of enthusiasm, according to data firm SimilarWeb, which tracks social media use.

By the end of July, Threads retained just 8 million daily active users, down 82% from its peak, according to data from research firm Sensor Tower first reported by CNN.

By comparison, X boasted 238 million users before Musk took the company private in October, the company said in an earnings report last year.

Threads faces formidable obstacles to overtaking X despite a flurry of changes imposed by Musk over the past year that have sent some users looking for an alternative, analysts previously told ABC News.

Still, Threads benefits from an army of potential users and the deep pockets afforded by parent company Meta, which also owns platforms Facebook, Instagram and WhatsApp. If any platform can overtake X, experts said, Threads may very well stand the best chance.

Over the weeks since a cage match was proposed earlier this summer, Zuckerberg has offered regular updates about the possible fight on Threads, where he boasts 3.3 million followers.

"Not holding my breath for Elon, but I'll share details on my next fight when I'm ready," Musk said in a post on Saturday.

The following day, Zuckerberg added in a Threads post, "I'm going to focus on competing with people who take the sport seriously."