Cold tidings for Caspian this morning, as Walt Disney Studios announced that they will not be co-producing and co-financing the adaptation of CS Lewis’ The Voyage of the Dawn Treader, the third of the Narnia films. This leaves Walden Media, the other big force behind the films, to find another partner if the film is indeed to hit screens in 2010.

Disney cited “budgetary and logistical” reasons for the move, which probably translates as “it’s very expensive, and the last one didn’t do so brilliantly at the box office”. Prince Caspian made a hair under $420 million at the worldwide box office, compared to $745 million for its predecessor The Lion, The Witch and the Wardrobe

Prince Caspian also cost in the region of $200 million, and given that The Voyage of the Dawn Treader would present more logistical difficulties given its sea-borne nature, the studio presumably thought it was a bit of a gamble – and the recent failure of other non-Potter kids fantasy films like The Golden Compass may further have put the wind up them. Disney’s withdrawal also casts doubt on the involvement of talent like planned director Michael Apted and screenwriter Steven Knight.

But hopefully all may not be lost! Walden Media works closely with Fox on most of its productions, so it may yet persuade Fox to step in. Watch this space for further news.