Charlie Hunnam, the British star of the forthcoming Fifty Shades of Grey movie, has shrugged off suggestions he might balk at the film's proposed graphic sex scenes.

Hunnam, 33, said the upcoming adaptation of EL James' bestselling "mommy porn" literary sensation, in which he will star as kinky billionaire Christian opposite Dakota Johnson's blushing virgin Ana, would be a walk in the park when compared to shoots for Channel 4 drama Queer as Folk 14 years ago.

"You know what, I had such a baptism of fire with regards to sexuality on camera at the beginning of my career," Hunnam told the Associated Press while promoting the season premiere of US TV series Sons of Anarchy. "I starred in the British Channel Four miniseries Queer as Folk, where I played a young, gay character, and there were some incredible, explicit sex scenes on that show. ... Now I am 16 years older and more mature so I don't anticipate them being too much of a problem. It's like anything else, just an exciting challenge."

Hunnam, who plays Jax Teller in Sons of Anarchy, the show about a California motorcycle club with criminal tendencies, also revealed his long-term partner Morgana McNelis might not be watching when Christian and Ana get it on for the first time.

"Of course, it's difficult being with an actor, you know?" said Hunnam. "She is required to share certain parts of me with the world that she wouldn't necessarily choose to do, but we have a great relationship, and she loves me and wants to be with me and we've been together a long time now, and I think she understands and has come to terms with the fact that there are certain elements of me that she is going to have to share. This is an extreme example of that, but thankfully we do have seven and a half years of history together, so it won't be a big problem."

James revealed last week that Hunnam and Johnson would star as business magnate Christian Grey and the young woman who becomes his well-renumerated sex slave, Anastasia Steele, in Nowhere Boy director Sam Taylor-Johnson's adaptation. The casting ended 18 months of furious speculation over the identities of the key cast members by fans of the knee-trembling novel and its two sequels, though there have subsequently been complaints from a group of fans who had hoped to see a different duo in the roles.

Dakota Johnson, the daughter of actors Don Johnson and Melanie Griffith, is best known for small roles in the Oscar-winning The Social Network and comedy The Five Year Engagement. Hunnam recently made the leap from TV to film after picking up strong reviews and decent global box office returns for Guillermo Del Toro's sci-fi action movie Pacific Rim. He starred as Nathan Maloney in Queer as Folk, Doctor Who writer Russell T Davies' pioneering miniseries about three young gay men living in Manchester's gay village at the turn of the century.

Fifty Shades of Grey, which will be Taylor-Johnson's second feature film as director, is due to shoot this autumn for an August 2014 release.

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