Philip Pullman's books have sold millions worldwide

Girls aged between nine and 13 are gathered in Cambridge, hoping to land the role of the book's young heroine Lyra Belacqua.

The film, directed by Anand Tucker, will be produced by New Line, which made the Lord of the Rings trilogy.

Further auditions are to be held in Oxford, Kendal and Exeter.

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Film-makers have said they are looking for a girl "who embodies Lyra's loyalty, bravery and mischievous nature" and who is not "immersed in the 21st Century".

Those who are successful will be invited to return for a second interview.

The film will be called The Golden Compass - the US title for Northern Lights - and could be released in September 2007.

It will follows Lyra as she stumbles into fantastical parallel universes on travels to save her best friend.

If successful, the two sequels, The Subtle Knife and The Amber Spyglass, will get the go-ahead.