San Sebastian has announced that Ben Stiller's film Tropic Thunder will be in official selection, out of competition, at this year's festival.

Stiller and actor Robert Downey Jr. will be at the Basque festival to present the film, which is being released in Spain by Paramount Pictures Spain on Sept 26.

Tropic Thunder is an action comedy about a group of self-absorbed actors who set out to make the most expensive war film ever but encounter real trouble in Southeast Asia.

The cast features Downey, Stiller, Jack Black, Tom Cruise, Nick Nolte, Matthew McConaughey and Steve Coogan.

The film was released by DreamWorks in the US yesterday.