Despite her character Dr Grace Augustine dying in the 2010 sci-fi epic, Weaver has revealed that Cameron plans to bring her back in some way.
"Don't worry, I will be back," Weaver told Coming Soon. "Jim [Cameron] says no one ever dies in science fiction.
"He's told me the stories for the next two movies and I have to say that they're absolutely wonderful and there's a real treat in store. Now we just have to make them."
The actress also suggested that Avatar 2 will begin filming sometime in 2012.
Wearver will next be seen opposite Twilight star Taylor Lautner in John Singleton's new thriller Abduction, due out in cinemas on September 23.