Hollywood studios face their first dual work stoppage in 63 years, forcing them to halt many productions across the United States and abroad.

The twin strikes will add to the economic damage from the writers walkout, delivering another blow to an industry struggling with changes to its business.

Both SAG-AFTRA – Hollywood’s largest union, representing 160,000 film and television actors – and the Writers Guild of America (WGA) are demanding increases in base pay and residuals in the streaming TV era plus assurances that their work will not be replaced by artificial intelligence (AI).

The actors’ union announced at a Thursday press conference that the strike will begin at midnight after its national board voted unanimously to authorise the walkout.

A deadline to reach a new contract expired on Wednesday.

Fran Drescher, former star of The Nanny TV show and the president of SAG-AFTRA, called the studios’ responses to actors’ concerns “insulting and disrespectful”.

“I am shocked by the way the people that we have been in business with are treating us,” Drescher said at the press conference at the SAG-AFTRA headquarters.

“I cannot believe it, quite frankly, how far apart we are on so many things, how they plead poverty, that they’re losing money left and right when giving hundreds of millions to their CEOs. It is disgusting.”

The Alliance of Motion Picture and Television Producers (AMPTP), the trade association that negotiates on behalf of Netflix Inc, Walt Disney Co and other production companies, said it was “deeply disappointed that SAG-AFTRA has decided to walk away from negotiations”.

The group said it had offered “historic pay and residual increases” and “a groundbreaking AI proposal that protects actors’ digital likenesses”.

Actors are worried that their digital images will be used without their permission or proper compensation.

“Rather than continuing to negotiate, SAG-AFTRA has put us on a course that will deepen the financial hardship for thousands who depend on the industry for their livelihoods,” the AMPTP said.

The strike by roughly 11,500 writers has sent late-night television talk shows into endless re-runs, disrupted most production for the northern hemisphere autumn TV season and halted work on big-budget movies.

The walkout by SAG-AFTRA, which represents actors from bit-part players to Hollywood’s biggest movie stars, will effectively shutter the studios’ remaining US-based productions of film and scripted television.

It will also hamper many overseas shoots involving SAG-AFTRA talent, such as Paramount Pictures’ sequel to Gladiator, which director Ridley Scott has been shooting in Morocco and Malta.

Some production work not involving SAG-AFTRA performers can proceed, such as location scouting or certain kinds of post-production editing.

But the loss of actors, who will also not do any promotional work for the film and television productions while on strike, will put more pressure on media companies to find a resolution.

Bob Iger, whose contract as Disney’s CEO was this week extended to the end of 2026, told CNBC on Thursday that the writers’ and actors’ unions had unrealistic expectations.

“It’s very disturbing to me,” Iger said, noting the entertainment industry’s ongoing recovery from the disruption of the COVID-19 pandemic.

“This is the worst time in the world to add to that disruption.”

Actors say the rise of the streaming era has made it harder to earn their livelihoods, especially for the many thousands of SAG-AFTRA members who are not household names.

“You have to make $US26,000 ($A37,800) a year to qualify for your health insurance and there are a lot of people who get across that threshold through their residual payments,” actor Matt Damon said at a promotional event held for the film Oppenheimer on Wednesday.

“There’s money being made and it needs to be allocated in a way that takes care of people who are on the margins.”

-AAP