Director James Cameron is delaying the first new Avatar film by a year as writing the three sequels is such a complex job.

Cameron plans to film the highly-anticipated sequels at one time and then release the three films over consecutive years, with the first one releasing in late 2017.

The first had been due in late 2016, but he said on Wednesday the writing process had proved to be “very involved” and that the initial target date was probably too ambitious.

“There’s a layer of complexity in getting the story to work as a saga across three films that you don’t get when you’re making a stand-alone film,” he said in Wellington, New Zealand, where he was helping promote the local film industry with other directors including Peter Jackson.

Cameron said the goal was to have the three scripts completed this month.

He’s leading the writing team.


“We’re writing three simultaneously. And we’ve done that so that everything tracks throughout the three films. We’re not just going to do one and then make up another one and another one after that,” he said.

“And parallel with that, we’re doing all the design. So we’ve designed all the creatures and the environments.” Cameron said he thought it was important that each film linked forward to the next one in a satisfying way but also came to a resolution so that the audience wasn’t left hanging.

Released in 2009, Avatar is the highest-grossing film in history, with a box office take of nearly $US2.8 billion ($A3.03 billion).

It was named best drama at the Golden Globes and won Academy Awards for cinematography, visual effects and art direction.

Cameron shot the original movie in New Zealand and is planning to shoot the sequels there. AAP

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