Cillian Murphy has spoken about his Dunkirk co-star Harry Styles, saying he's a "really cool kid" who is sure to "do fantastically" in his movie debut.

The Irish actor, who stars in Christopher Nolan's film alongside Tom Hardy and Mark Rylance, says he is positive the One Direction singer will do a good job because the director only casts "talented people" in his movies.

When asked by ShortList magazine what tips he would give the 22-year-old boybander, Murphy replied: "It's not my job to give advice to people like that. Chris Nolan cast Harry Styles, and Chris Nolan knows what he's doing.

"He's not going to cast someone that doesn't have talent. I've hung out with Harry and he's a really cool kid, and I'm sure he'll do fantastically."

He added: "But no. I hope I'm not in the 'elderly actor giving advice' bracket yet. That would give me a pain in the hole, to be honest."

The 40-year-old Cork-born actor went on to praise his Dunkirk director Nolan, whose previous works include The Dark Knight trilogy and Inception, saying he's one of the "greatest filmmakers" of all time.

"I love that Chris is making it because he's one of the greatest filmmakers we have," Murphy said. "Every great filmmaker needs a war movie. It seems to be a part of the rite of passage."

Dunkirk is scheduled for release in summer 2017.

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