James Cameron is planning to convert Titantic into 3D

Avatar will be re-released this summer with an additional six minutes of footage, its director James Cameron has said in a newspaper interview.

"We were sold out of our Imax performances right up to the moment until they were contractually obligated to switch to Alice in Wonderland.

"So we know we left money on the table there," Cameron told the LA Times.

Cameron also said the Avatar sequel will be centred on the ocean on the planet Pandora.

The ocean would be as "equally rich and diverse and crazy and imaginative," he said.

The award-winning filmmaker claimed the release of Alice in Wonderland and Clash of the Titans in 3D, so soon after Avatar came out, meant there were not enough cinemas available to give Avatar a proper run.

By the time the film is re-released, it will also be out on DVD but Cameron believe those who have already seen Avatar at home will still want the big screen experience.

Tim Burton's Alice in Wonderland had record opening takings for a 3D movie when it was released in March.

Avatar became the fastest movie ever to achieve $1bn (£625.6m) in ticket sales around the world earlier this year.