Emily Blunt and Matt Damon walk out of Oppenheimer premiere due to Sag-Aftra strike

Cillian Murphy, Florence Pugh, Robert Downey Jr and others leave to join historic Hollywood strike

From left, Matt Damon, Emily Blunt, Cillian Murphy and Florence Pugh attend the UK premiere of Oppenheimer in London. EPA

Cillian Murphy, Emily Blunt and Matt Damon were among stars who staged a walkout from the UK premiere of Oppenheimer to join the SAG-AFTRA strike on Thursday.

The launch of Christopher Nolan's historical epic started an hour ahead of a SAG-AFTRA press conference in Los Angeles, which began a historic strike by the actors' union in Hollywood.

The expected announcement cast a shadow over the London film premiere at the Odeon Luxe in Leicester Square, with the film's major stars including Florence Pugh, Robert Downey Jr, Sir Kenneth Branagh and Rami Malek leaving before the screening of the film.

“I have to acknowledge the work of our incredible cast, led by Cillian Murphy,” Nolan said.

“Unfortunately, they are off to write their picket signs for what we believe to be an imminent strike by SAG, joining one of my guilds, the Writers Guild, in the struggle for fair wages for working members of their union.”

Pugh told PA that the cast felt lucky to attend the premiere before the strike was announced, but they were proud to strike.

“We feel both lucky, that we got to squeeze this in, and also lucky that we get to stand by our peers in a decision that is made,” she said.

Ahead of the screening, Blunt warned that the cast would be leaving “in unity” if the strike was announced.

“I hope everyone makes a fair deal and we are here to just celebrate this movie,” she told Deadline in an interview. “We'll be leaving together as a cast in unity with everyone.”

The strike news comes after the US union and Hollywood studios failed to reach an agreement after more than four weeks of negotiations, with actors wanting better pay and increased safeguarding around AI rights among their demands.

It is now expected that the strike will affect coming award shows, premieres, events and film festivals around the world, including the Toronto and Venice film festivals, and the 75th Emmys.