Kiwi director Peter Jackson has been on a casting trip in the United States for The Hobbit, according to reports, even though the movie hasn't been given the official greenlight yet.

According to website Hollywood Reporter, Mr Jackson has been quietly meeting with actors in Los Angeles, New York and the United Kingdom to discuss potential roles in The Hobbit, the future of which has been in doubt since the shock resignation of director Guillermo del Toro at the end of May.

Hollywood Reporter said Mr Jackson had been in LA since Saturday working with casting director Victoria Burrows on assembling "a large, international cast" for the project.

The site quoted sources as saying that Mr Jackson was close to signing a deal with Warner Bros to direct the two-part J.R.R Tolkien adaptation, but the "sticking point" was the dire financial situation at MGM, which co-owns the rights to the film version of The Hobbit.

- NZ Herald staff