Dominic West has said it was "incredibly emotional" after Maggie Smith told him the new Downton Abbey film would be her final acting job – only for her to later land a new film role.

The Wire actor joins the cast of the hit period drama for the second film, Downton Abbey: A New Era, portraying a silent film star appearing in a movie being shot at the stately home.

He said he was thrilled to share the screen with double Oscar winner Maggie, who is best known for roles including in the Harry Potter franchise, Sister Act, A Room With A View, Gosford Park and The Prime of Miss Jean Brodie, and who plays the Dowager Countess Violet Crawley in the long-running series.

But he then became dismayed when she told him the film would be her last.

Dominic West

West told a press conference: "I sat next to her around that famous table for two or three days and got to just chat to her and listen to her hilarious jokes and sly remarks.

"She said at one point that she's going to throw in the towel now. She said: 'That’s it. I’m not going to do any more.’ And I said: ‘What? Acting?’ and she said: ‘Yeah, no more acting.’

"I said: ‘Theatre as well?’ and she said: ‘No, I’m not doing theatre either, and this will be my last job.’ And that was incredibly emotional.

"Actually I was in the scene that she shot last in the show and I thought: ‘Oh my god, I’m witnessing history here’ and it was incredibly emotional.

We need your consent to load this YouTube contentWe use YouTube to manage extra content that can set cookies on your device and collect data about your activity. Please review their details and accept them to load the content.Manage Preferences

"And I was talking to her afterwards in the make-up trailer, and it was very moving that this great, great actress wasn’t going to act any more.

"And then I went back the following week, and I said: ‘It’s so sad Maggie’ and she said: ‘Nonsense!’ and she’s booked another film. She starts next week."

The new Downton Abbey film sees stars including Hugh Bonneville, Elizabeth McGovern, Michelle Dockery, Laura Carmichael and Joanne Froggatt all reprise their roles, while Laura Haddock and Hugh Dancy also join the cast.

Downton Abbey: A New Era is released in cinemas on April 29.