Creator, writer and director of the 'Avatar' franchise James Cameron has revealed he may not have the time to direct the 4th and 5th instalment, amongst his interest in other projects.

"The 'Avatar' films themselves are kind of all-consuming," Cameron admitted in an interview with Empire.

"I've got some other things I’m developing as well that are exciting. I think eventually over time – I don’t know if that’s after three or after four – I'll want to pass the baton to a director that I trust to take over, so I can go do some other stuff that I’m also interested in. Or maybe not. I don’t know."

'Avatar' released in 2009 and is the highest-grossing film ever made, with a grand total of $2.8 billion at the global box office. The film is set on the lush moon of Pandora, hundreds of years in the future, where humans are mining for the rare mineral unobtanium. Humans come into conflict with the native Na'vi, whose habitat is being threatened.

The first of four sequels sees the original cast of Zoe Saldana, Sam Worthington, Sigourney Weaver, Stephen Lang, Joel David Moore, CCH Pounder and Giovanni Ribisi return. Additional casting includes Kate Winslet, Jemaine Clement, Cliff Curtis and Edie Falco.

"Everything I need to say about family, about sustainability, about climate, about the natural world, the themes that are important to me in real life and in my cinematic life, I can say on this canvas," the 67-year-old filmmaker explained.

"I got more excited as I went along. Movie four is a corker. It’s a motherfucker. I actually hope I get to make it. But it depends on market forces. I really hope that we get to make four and five because it’s one big story, ultimately."

Honestly, James, we wouldn't worry about all that yet, let's get the next two films out first.

'Avatar: The Way of the Water' releases in cinemas on December 16.