Florence Pugh joined her Oppenheimer cast members at the Oscars as Christopher Nolan’s epic biopic won seven prizes.

The film about J Robert Oppenheimer, the theoretical physicist described as the father of the atomic bomb, was named best picture, while its star, Cillian Murphy, won best actor, the first Irish winner of this award.

Mr Nolan also ended his 22-year wait for an Academy Award with the London-born filmmaker previously being nominated six times but had never won an Oscar for directing until Sunday’s ceremony.

Ms Pugh played the part of Jean Tatlock in the film showing her affair with the theoretical physicist.

The Oxford-born actress previously admitted Mr Nolan apologised to her over the size of her role but she had no qualms over the part.

Oxford Mail: Florence Pugh attending the Vanity Fair Oscar Party

Robert Downey Jr was named best supporting actor for his turn as Lewis Strauss, head of the Atomic Energy Commission, securing him his first Oscar win.

The film was also celebrated for its editing, score and cinematography.

The best picture prize, the final trophy of the night, was handed out by veteran actor Al Pacino, who announced the winner in an unconventional manner without the customary fanfare.

Collecting his directing trophy, Mr Nolan thanked his wife and producer of the film, Emma Thomas, as well as Mr Murphy.

Oxford Mail: Christopher Nolan (Chris Pizzello/PA)

Mr Nolan said: “Thank you for those who have been there for me and believed in me my whole career.”

He added: “To the Academy, just to say movies are just a little bit over 100 years old… I mean imagine being there 100 years into painting or theatre.

“We don’t know where this incredible journey is going from here. But to know that you think that I’m a meaningful part of it means the world to me. Thank you very much.”

Mr Murphy, 47, kissed his wife, artist Yvonne McGuinness, before heading to the stage, where he said making the film had “been the wildest, most creatively satisfying journey”.

“I am a very proud Irishman standing here tonight,” he added.

Acknowledging “we are all living in Oppenheimer’s world now”, he added: “I would like to dedicate this to the peacemakers of the world.”

At the end of his speech, he spoke in Irish, saying “go raibh maith agat” which means “thank you very much”.

However, it has not all been smooth sailing as the premiere in London meant that stars including Emily Blunt, Mr Downey Jr, Mr Murphy and Ms Pugh staged a walkout when the Hollywood union Screen Actors Guild – American Federation of Television and Radio Artists (Sag-Aftra) called a strike.