LAS VEGAS — The labor union representing tens of thousands of Las Vegas hospitality workers announced early today that it had reached a tentative deal with casino giant Caesars Entertainment, a major breakthrough that could help avert an unprecedented strike at more than a dozen hotel-casinos on the Las Vegas Strip.

The announcement came after several months of tense negotiations and just days before the Culinary Workers Union’s deadline for a strike. The union said in a post on X, formerly known as Twitter, that the agreement toward a 5-year contract for about 10,000 workers came after 20-straight hours of negotiations.

A walkout could still happen if deals aren’t reached by 5 a.m. Friday with MGM Resorts International and Wynn Resorts. But the tentative agreement with Caesars could provide the momentum needed for the Culinary Union to win new 5-year contracts for all 35,000 of its members who have been working under expired contracts at 18 properties owned or operated by the casino companies.

Negotiations with MGM Resorts are scheduled for today and Wynn Resorts on Thursday.

Caesars did not immediately comment on the tentative agreement, but CEO Thomas Reeg said in a recent earnings call, “When we reach an agreement on the contract, it’s going to be the largest increase that our employees have seen in the four decades since we started interacting with the Culinary Union.”

Bethany Khan, a spokesperson for the union, said terms of a deal with Caesars would be pending approval from the union’s rank and file and would be made public once approved.

A strike would cut to the heart of the city’s economic backbone and significantly disrupt operations at some of the most recognizable Las Vegas hotel-casinos as they prepare to host hundreds of thousands of people for next week’s Formula 1 debut on the Strip.

It would be the latest in a series of high-profile actions around the country in what has been a big year for labor unions, including walkouts in Hollywood and UPS’ contentious negotiations that threatened to disrupt the nation’s supply chain. It would also follow hospitality workers walking off the job last month at Detroit’s three casinos, including MGM Grand Detroit.

“No matter if you’re auto workers, if you’re teachers, if you’re writers, if you’re screenwriters, the whole concept is we just want a fair way of making a living,” said Leslie Lilla, a cocktail server at the Bellagio. “We want to provide for our families, so that is coming across loud and clear in America.”

The race course for the inaugural Las Vegas Grand Prix will feature sweeping views of many of the casinos at risk of walkouts if they don’t strike deals with the union before Friday morning. That includes the Bellagio, Paris Las Vegas and MGM Grand.

The other properties that could be impacted by a strike are the Wynn and Encore resorts, as well as MGM Resorts International’s Aria, Excalibur, Luxor, Mandalay Bay, New York-New York and Park MGM.

The hospitality workers say they are willing to strike for as long as it takes to get fair contracts — from the housekeepers and utility porters who work behind the scenes to keep the Strip’s mega-resorts humming, to the bartenders and cocktail servers who provide the customer service that has helped make Las Vegas famous.

“We really don’t want to do this, but if we have to, we will,” Leain Vashion, a bell captain at Paris Las Vegas, said earlier Tuesday during a break in negotiations with Caesars. “We will go on strike for our families, for health care, for a pension and for dignity in the workplace.”

Bargaining has been underway since April over pay, benefits, job security and working conditions, but negotiations have ramped up in recent months after an overwhelming majority of union members voted in September to authorize a strike.

The vote was followed by large-scale rallies on the Strip, including one last month that ended with the arrests of 58 workers who sat in the street and halted rush-hour traffic on one of the most recognizable stretches of the Strip. The workers called it a show of force ahead of any potential strike.

As that rally began, two visitors from Missouri, Cindy Hiatt and Michelle Shirley, told The Associated Press they won’t return to Las Vegas again during any strike by hotel workers.

“The hotels are going to have to realize that they’re not going to have people wanting to come to Vegas without these workers,” Hiatt said.

Members currently receive health insurance and earn about $26 hourly, including benefits, Khan said. The union hasn’t revealed what it has been seeking in pay raises because, Khan said, “we do not negotiate in public,” but the union has said it is asking for the largest wage increases ever negotiated in its history.

The workers have also said they want better job security amid advancements in technology, as well as stronger security protections, including more safety buttons on casino floors.