The union representing thousands of striking television and movie writers denied a waiver that Broadway officials had sought that would have allowed the Tony Awards ceremony to proceed with a live televised broadcast on its scheduled date of June 11, two people briefed on the decision said on Friday night.

The denial by the union, the Writers Guild of America, described by people who were granted anonymity to disclose confidential discussions, is imperiling one of Broadway’s biggest nights — a key marketing opportunity that is even more crucial in the fragile post-shutdown theater economy. Industry leaders say that without the ability to reach the broad audience that tunes into a Tony Awards broadcast, several of the newest musicals are likely to close.

Broadway boosters are still hoping that over the weekend the writers’ guild might be persuaded to change its mind. But industry leaders are acknowledging that such a reversal seems unlikely. Without a waiver from the writers’ guild, a live broadcast ceremony is essentially impossible because much of Broadway, including nominees and presenters, would refuse to cross a picket line.

The management committee of the Tony Awards, which is the group charged with overseeing the broadcast, has scheduled an emergency meeting on Monday at which it will discuss how to proceed.

One option would be to postpone the entire event until after the strike is settled, in which case some money-losing Broadway shows would most likely close rather than hang on in the hopes of an eventual boost from a broadcast. Another would be to hand out the awards in June in some non-televised fashion, which would significantly reduce the marketing value of the awards. But they could try to make up for that by staging some kind of razzle-dazzle song-and-dance-heavy broadcast after the strike ends.

None of the parties would speak on the record on Friday night, but several people close to the discussions described the state of affairs after The Hollywood Reporter reported that the waiver had been denied.

For Hollywood, the Tony Awards are not a front-burner issue — it is a niche ceremony watched last year by 3.9 million people, which is fewer than other awards ceremonies like the Oscars (18.7 million) or the Grammys (12.5 million).

But for Broadway, the stakes are enormous. The Tony Awards are the industry’s biggest marketing moment — a chance to introduce viewers to shows they have not heard of, and to remind them of the joys of musical theater — and that kind of reach is especially important now, with Broadway attendance yet to reach prepandemic levels. Four of the five nominees for best new musical are not selling enough tickets to cover their running costs many weeks, and all could use the box office boost that a win, or even a well-performed number on the awards show, often provides.

“The Tony Awards is the biggest commercial for the industry at large, and for a show like mine, which is unbranded and just at the stage where we are finally starting to see some lifeblood, it would be devastating to not be able to be part of this,” Mike Bosner, the lead producer of “Shucked,” one of the five shows vying for the coveted best new musical award, said before the denial was announced.

“Our whole timing of when we opened the show was based on being part of the ramp-up to the awards season, when there are a lot of eyeballs on the show and there’s national exposure,” he said.

Even before news of the W.G.A.’s decision to deny the waiver spread, some producers were pessimistic. “My guess is that there won’t be a broadcast,” Robert Greenblatt, one of the producers of “Some Like It Hot,” which is also a nominee for best new musical, said earlier. Greenblatt is familiar with all sides of the issue — he is not only a frequent Broadway producer, but also a former chairman of NBC Entertainment and WarnerMedia.

If the Tonys are delayed or derailed, it will damage many shows. “Particularly this season, when we’re still recovering from the Covid shutdown, it would be especially devastating to not have that opportunity — to not be able to showcase how many great and diverse plays and musicals are on Broadway right now,” said Eva Price, a lead producer of “& Juliet,” another contender for best new musical.

Already, the W.G.A. strike has affected one awards show — last weekend’s MTV Movie & TV Awards. The host, Drew Barrymore, dropped out in solidarity with the union and the ceremony turned into a pretaped affair after the W.G.A. said it would picket.

On Wednesday, with the prospect of hundreds of demonstrators marching on picket lines, Netflix abruptly announced it was canceling a major in-person Manhattan showcase it was staging for advertisers next week, and turning it into a virtual event instead.

Ted Sarandos, the co-chief executive of Netflix, also said he would not attend the upcoming PEN America Literary Gala at the American Museum of Natural History, a marquee event for the literary world that was scheduled to honor him. In a statement, Mr. Sarandos said it was best if he pulled out “given the threat to disrupt this wonderful evening.”

In 2008, the last time the writers were on strike, organizers of the Golden Globes were forced to cancel the awards ceremony after the W.G.A. was actively organizing demonstrations and actors said they would not cross any picket lines. Winners were revealed in a news conference instead. But during that strike the W.G.A. did grant waivers to some televised ceremonies, including the Screen Actors Guild Awards.

The organizations that present the Tony Awards, the Broadway League and the American Theater Wing, declined to comment; they are said to be closely monitoring the situation but unsure of how to proceed. Representatives for the W.G.A., and CBS, the Tonys’ longtime broadcaster, also declined to comment.