LONDON (AFP) - New films based on the works of J.R.R. Tolkien are only possible with the permission of the author's estate, Hobbit director Peter Jackson said on Tuesday.
The New Zealand director was speaking in London a day after the premiere of The Hobbit: The Battle Of The Five Armies, the final instalment in a trilogy that followed Jackson's successful Lord Of The Rings series.
"The Tolkien estate owns the writings of Professor Tolkien. The Hobbit and The Lord of the Rings were sold by Professor Tolkien in the late sixties, the film rights," Jackson said at a press conference.
"They are the only two works of his that have ever been sold... So without the cooperation of the Tolkien Estate, there can't be any more films."
Any deal could be uncertain, as the novelist's son and literary executor Christopher Tolkien was critical of the "commercialisation" of his father's work in a 2012 interview with French newspaper Le Monde.
"Tolkien has become a monster, devoured by his own popularity and absorbed by the absurdity of our time," Christopher Tolkien was reported to say.
"The chasm between the beauty and seriousness of the work, and what it has become, has overwhelmed me. The commercialisation has reduced the aesthetic and philosophical impact of the creation to nothing.
"There is only one solution for me: to turn my head away."
Working from Tolkien's notes, Jackson added storylines and characters into the film which that did not appear in the original book, such as the woodland elf Tauriel, played by Lost star Evangeline Lilly.
British actor Orlando Bloom, who plays elf Legolas in the film, said how fans would react to such additions was a worry.
"It was a concern as to whether or not the fans, how they would feel about bringing characters in that aren't in the book," Bloom said.
However, the added back story "worked really well" in the end, he added.
Jackson, when asked about future film projects, joked that after spending over a decade bringing to life the world of Tolkien's Middle Earth, he could now "go to the beach".
He added, however, that he would soon be working on an extended cut of The Hobbit finale with additional material for later release.
The longer version will include about 30 minutes of additional material to the two-hour and 24-minute length of the standard version of the film.
Shot in 3D, at a vivid 48 frames per second, the film will appear in cinemas around the world from Dec 10.