Warner, known for his work in films such as Titanic, Star Trek, The Omen, Tron and Planet of the Apes, will star in a historical episode written by Mark Gatiss and directed by Douglas MacKinnon.
In 2009, the actor played Lord Azlok in the Doctor Who animated episode Dreamland and has also featured in a number of Big Finish audio dramas.
Liam Cunningham will also guest star in the story with Warner. Cunningham currently has a role in Game of Thrones, with previous film roles in The Mummy: Tomb of the Dragon Emperor and Clash of the Titans.
The episode will be part of the eight episodes of series seven which will be broadcast on BBC One in early 2013.
More exclusive information regarding the new series is available in Doctor Who Magazine 449 - on sale now at the price of £4.50.