James was in attendance at Vanity Fair's Academy Awards party in Hollywood on Sunday (February 24), where she spoke about the heavily-rumoured cast of the upcoming film.
"We don't even have a filmmaker... so we are still a long way away from casting," the writer admitted to Page Six.
James then teased: "I have some ideas... but it may not be who people expect."
There has been tremendous speculation about which actors will play Fifty Shades of Grey's Ana Steele and bondage enthusiast Christian Grey in the film.
Henry Cavill, Ian Somerhalder and Jake Gyllenhaal have all been tipped as frontrunners to play Grey, while Chace Crawford recently threw his name into the ring as well.
Potential candidates to play Ana Steele include Mila Kunis, Shailene Woodley and Game of Thrones actress Emilia Clarke.
Kelly Marcel will be adapting Fifty Shades of Grey for the screen, having previously penned episodes of Terra Nova and the upcoming film Saving Mr Banks.
50 Shades of Grey: The rumoured cast in pictures:
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