Ian Somerhalder.
Vampire Diaries actor Ian Somerhalder at the 2013 Comic Con International in San Diego, California.

Vampire Diaries star Ian Somerhalder, a fan favourite for the role of Christian Grey in the film version of EL James's best-selling erotic novel Fifty Shades of Grey, is reportedly out of the casting list. Us Weekly claims James, who was at the Comic-Con festival in San Diego, confirmed the news.

An insider told the publication, "E.L. was at a Comic-Con party July 20 telling people the part won't go to Ian." The news follows speculation the 34-year-old American actor broke off with girlfriend and Vampire Diaries co-star Nina Dobrev, over the character of Grey.

In March, during an appearance on American television show What Watch Happens Live, Somerhalder declined to comment to host Andy Cohen on casting choices.

"I think they have a very big job ahead of them, casting this role," he said, "So, I can't say anything other than, it's a very interesting story and whoever plays that role is going to have a lot of fun rehearsal time."

Meanwhile, 28-year-old American actor Garett Hedlund has reportedly also been overlooked. The Tron: Legacy star is believed to have backed out over the demand to commit to the entire trilogy.

"Doing a possible trilogy was too big a commitment, and producers wouldn't let him do just one film," a source explained.

In other news, it has been announced that the film will release in the United States on 1 July next year. British visual artist and filmmaker Sam Taylor-Johnson will be directing a script written Kelly Marcel, whose other credits include Saving Mr Banks (to release later this year and starring Tom Hanks, Colin Farrell and Emma Thomson).

Dana Brunetti and Michael De Luca (producers of Oscar-winning The Social Network) will work behind the scenes, with James as well.

"I saw both of her films, and I was blown away. Simple," James praised Taylor-Johnson when she spoke to Vulture, "She's creative, incredibly talented, she's got an extraordinary eye. She had a good idea about the whole Fifty experience, she understands it. And I thought, There's a woman I can go and get drunk with."