Sam Worthington is yet to sign any deal for the Avatar sequels according to sources. The 34-year-old actor played the lead role of Jake Sully in the original film.

Award winning director James Cameron has agreed to write scripts for the films in early 2011 however producers have yet to confirm if original cast members will be returning.

"The whole story was built around Jake [Worthington's character] - it's hard to see where Cameron can take it without him." a source told the Heard Sun.

The English born actor has previously expressed an interest in future Avatar projects saying: "The plan was that if it made a billion we'd give an undertaking but we'd only do it if it challenged Jim."

The science fiction sequels are set to be released in December 2014 and December 2015.