Here is the official statement:
"Slowly but surely, Peter Jackson has managed to secure the return of the majority of the major stars from The Lord of the Rings franchise for his soon to be shooting prequel, based on J.R.R. Tolkien's The Hobbit.
Sir. Christopher Lee had been in talks to reprise his role as the wizard Saruman and it now looks certain, providing that he is in good health, that he will be appearing in the movie."
Starring Martin Freeman, Hugo Weaving, and Andy Serkis (plus a whole load of other returning stars!) - The Hobbit, Part 1 shuffles into theaters 19th December 2012!