The singer is playing a young soldier in the film, based on the Dunkirk evacuation in World War II.
He was met with praise ahead of the premiere of the eagerly anticipated movie, Dunkirk, earlier this week.
They penned: '#Dunkirk packs a wallop but a VERY different Nolan movie. Nolan said: 'I don't think I was that aware of how famous Harry was.
He has become known for his bold fashion choices of late.
"Harry and Tess haven't seen each other for a number of weeks.
They're both constantly travelling the world," a source told the publication.
No."I don't feel like it's something I've ever felt like I have to explain about myself."Meanwhile, Hazza has said that when Simon Cowell listened to 'Sign of the Times' he got in touch with Harry and had only nice things to say about it."He said he really liked it and he was very proud of me," Harry recalled. Not like past phone calls haven't been friendly, but I didn't get that nervy 'the boss is calling me' feel, which was nice."However, the same perhaps can't be said about Harry's relationship with Zayn Malik – as it appears the pair rarely speak to each other these days."Not so much," he said.
PHOTOS: Check out the latest pics of Harry Styles Harry rocked a newsboy cap, tan jacket with a rainbow design on the back, skinny jeans, and brown boots for part of the show.
Harry looked absolutely sensational as he posed alongside director Christopher Nolan and actors Tom Glynn-Carney, Fionn Whitehead, Emma Thomas and Jack Lowden.
The boybander, who is know for favouring a more kooky look, was dressed to perfection in the eye-catching shirt which was slightly unbuttoned at the top.
Harry Styles has revealed he plans to tour his forthcoming solo material.
The One Direction singer appeared on the Graham Norton Show to perform his debut solo single Sign of the Times.
"Tess realised she still had feelings for her ex after splitting from him to date Harry and has apologised to him for her romance with the singer." The source continued, "It will take a while for Tess to build back his trust but they have been getting on as normal.