For months, the chatter in Silicon Valley has centered on whether or not Mark Zuckerberg and Elon Musk would truly take part in a “cage match” as they mentioned they might. But after a flurry of exercise and guarantees from either side, it regarded as if the momentum behind the mega-mogul face-off had fizzled out.

It’s changing into clearer what the holdup could also be: Mr. Musk.

On Sunday, Mr. Zuckerberg, chief government of Meta, mentioned that he recommended the 2 males take part in an final combating match on Aug. 26, however that Mr. Musk — who owns X, the corporate previously referred to as Twitter — had but to substantiate the date.

Mr. Zuckerberg’s feedback adopted an early-morning post on X from Mr. Musk, who mentioned that he deliberate to livestream the cage match on X in addition to elevate cash for charity by means of the platform.

“I’m not holding my breath,” Mr. Zuckerberg mentioned afterward Sunday in a post to Threads, a rival platform he rolled out last month that some had known as the Twitter killer.

The two billionaires have engaged in a back-and-forth recreation of each skilled and private one-upsmanship for a lot of the previous 10 years. That rivalry has solely elevated in latest months, as Mr. Zuckerberg rapidly spun up Threads after he witnessed the difficulties Mr. Musk had in his takeover of Twitter.

Threads noticed an early burst of enthusiasm, breaking information for the quickest variety of downloads for any app in historical past in its first week. The firm mentioned it should now deal with including new options that maintain folks coming again because the preliminary pleasure has cooled. That has put strain on Mr. Musk to proceed introducing new options to X, which he has indicated he wants to position as an “everything app” akin to these widespread in China, Japan and South Korea.

Their brinkmanship got here to a head in June, when Mr. Musk, in a reply to somebody on Twitter, mentioned that he would battle Mr. Zuckerberg in a bodily cage match. The subsequent day, Mr. Zuckerberg confirmed he was greater than keen, and the 2 males entered into talks presided over by Dana White, president of the Ultimate Fighting Championship. It appeared as if the battle “might actually happen,” Mr. Musk later mentioned in a web-based dialogue.

But these talks seem to have stalled in latest weeks, at the same time as Mr. Musk sometimes joked on-line that he was training for the match with friends. In response, Mr. Zuckerberg posted pictures of his personal coaching routine with skilled Brazilian jiu-jitsu fighters. In July, Mr. Zuckerberg posted a photo of himself shirtless after a coaching match, boasting a newly chiseled physique and affirming his zeal for the game.

A spokesperson for Meta declined to remark. Mr. Musk didn’t reply to a request for remark.

On Sunday, Mr. Zuckerberg mentioned that Mr. Musk’s proposal to stream the battle on X didn’t appear prudent, suggesting as a substitute that they do it on a platform that was “more reliable” and in a position to straight elevate cash for charity. (Mr. Musk’s platform suffered technical points and glitches over the previous 12 months, together with problems when he livestreamed his look with Gov. Ron DeSantis of Florida, who used Twitter to announce his candidacy for president.)

“I’m ready today,” Mr. Zuckerberg said on Sunday. “I love this sport and will continue competing with people who train no matter what happens here.”

Ryan Mac contributed reporting.