Cillian Murphy thinks Harry Styles will do ''fantastically'' in 'Dunkirk' - without his advice.

The 40-year-old actor - who has a supporting role in the movie alongside Tom Hardy and Mark Rylance - thinks the One Direction star will make a good job of his debut movie role because director Christopher Nolan only allows ''talented people'' in his films.

Asked what tips he would give the 22-year-old singer, he said: ''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.

''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.''

Meanwhile, the 'Peaky Blinders' star has hailed Nolan as one of the ''greatest filmmakers'' of all time.

He told ShortList magazine: ''I love that Chris is making it because he's one of the greatest filmmakers we have.

''Every great filmmaker needs a war movie. It seems to be a part of the rite of passage.''

And Cillian is not the only 'Dunkirk' star who gets on well with Harry, Mark Rylance is also a massive fan, along with the rest of the cast and crew.

A source recently said: ''Mark Rylance really gets on well with Harry. They have been known to enjoy a bottle of wine together some evenings when they aren't filming.

''The hair and make-up team love him too because he's very polite. One time he even made the effort to thank the catering department for making what he called 'fantastic food'. He's such a gent.''

It was recently revealed that Harry has hired a ''full-time bodyguard'' to protect him from his fans on the set of the movie.

A source said: ''Harry has to have a full-time bodyguard to follow him around because fans have been breaking onto set to see him. He's the only person who has a security guard at his side round the clock, but his minder follows him home too.''