BBC1 sci-fi drama Outcasts is being moved from 9pm to a Sunday late-night slot after disappointing ratings.

In what appears to be the first major scheduling change since new BBC1 controller Danny Cohen took over, after next Monday's 9pm instalment the series will move to 10.25pm from Sunday 27 February. It is unusual for schedulers to switch a programme from one slot to another so close to transmission.

Last night it drew 2.6 million viewers, against tough competition from Channel 4's Big Fat Gypsy Weddings and ITV1's The Brit Awards 2011. Big Fat Gypsy Weddings was watched by 6.5 million, while the Brits averaged 4.8 million.

Outcasts launched with 4.4 million last Monday, but the show's audience has declined for each episode since then.

The BBC drama controller, Ben Stephenson, said the move did not signal that the BBC does not want to take risks and said the show had attracted a "loyal, core audience".

"BBC1 and BBC drama support creative risk. Sometimes this means that talented people make shows that don't engage enough of the audience. I have so much respect for any writer who has the nerve and confidence to create their own original world and serve it up to an audience," Stephenson added.

"It's highly important to me to support them no matter how the project is received, whilst primarily always trying to engage the widest possible audience."

The BBC had high hopes for Outcasts, which featured an impressive cast including former Spooks actress Hermione Norris and Ugly Betty star Eric Mabius.

The eight-part series launched on 7 February with 4.4 million viewers, but then followed an unusual scheduling pattern, with the second episode airing the following night and drawing 3.3 million. The third episode this Monday attracted 2.9 million.

Filmed in South Africa, Outcasts is made by Kudos, the producer of other BBC drama hits such as Spooks and Hustle.

Kudos is owned by Elisabeth Murdoch's production business Shine, which is understood to be in talks with her father's News Corporation on a possible buyout.

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