Hollywood actors' strike: Why Sag-Aftra industrial action 'could come to UK’ as Cillian Murphy, Emily Blunt and Florence Pugh stage walkout

Oppenheimer director Christopher Nolan has said he will "absolutely" not work on another film until the Hollywood actors' strike was resolved

The Hollywood actors' strike could be moving across the Atlantic if US production companies shift filming to the UK because of the industrial action taken by their American counterparts, a British union has said.

Equity, which represents more than 47,000 performers in the UK, says the union stands in solidarity with US actors who are striking in a dispute with Hollywood studios.

The union, which is not striking, told US companies it would be keeping a "very close eye" on any attempts to move productions to the UK due to the action called on Thursday evening.

Matt Damon, Emily Blunt, Cillian Murphy and Florence Pugh attend the 'Oppenheimer' UK Premiere at the Odeon Luxe Leicester Square. Picture: John Phillips/Getty Images

Robert Downey Jr, Cillian Murphy, Emily Blunt and Florence Pugh staged a walkout of the London premiere on Thursday of historical epic Oppenheimer due to the strike.

Equity's general secretary Paul Fleming said he was "hopeful" a settlement with members of the Screen Actors Guild – American Federation of Television and Radio Artists (Sag-Aftra) would come soon.

He said: "Anything that happens on a British contract, we're looking to next year's negotiations.

"The one exception is if there are productions from the United States that attempt to avoid the industrial action by relocating to the United Kingdom – we are keeping a very, very close eye on them. We do reserve the right to use British legislation to take British industrial action in those sorts of instances and that will be on a case-by-case basis.

Members of the Writers Guild of America East are joined by SAG-AFTRA members as they picket at the Warner Bros. Discovery NYC office. Picture: Michael M. Santiago/Getty Images

"I can't say the law here is significantly more restrictive than the United States in terms of how you take a strike, but we will be clamping down on those sorts of productions.

"And also a huge issue for Sag-Aftra members for the last month or so has been an adverts for British productions which say 'no Sag-Aftra member need apply'.

"Well, I'm sorry, this contract is not in dispute and discrimination on the grounds of a trade union membership is illegal in this country, irrespective of where that trade union is based.

"So that's where things might get a bit more heated this end."

It comes amid the ongoing industrial action by more than 11,000 members of the Writers Guild of America (WGA), who began industrial action on May 2.

Among the productions in the UK that could be affected by the strike action is the filming of Deadpool 3, starring Hollywood actors Ryan Reynolds and Hugh Jackman.

House Of The Dragon series two with Matt Smith and Emma D'Arcy could also be affected, alongside the second series of The Sandman with Tom Sturridge and the fourth series of Slow Horses with Academy Award winner Gary Oldman.

Speaking about the impact on the British film industry, Mr Fleming said it depended on whether an actor was under an Equity or Sag-Aftra contract.

He said: "So a Sag-Aftra or an Equity member working on an Equity contract is not on strike because that's not the contract in dispute.

"Where it gets a little bit more complicated is that there are some Sag-Aftra members around the world who are working on Sag-Aftra contracts alongside others who are on Equity contracts.”