Channel 4 is running advertisements on its Big Brother "catch-up" online video service for the first time.

The service, which allows viewers to see up to four minutes of highlights footage from the show each day, features ads from Warner Bros and the Australian Tourist Board.

Warner Bros is running a 30-second spot, adapted for the site by PHDiQ, the interactive media division of buying agency PHD, to promote the launch of disaster movie remake Poseidon.

It is predicted that by the time of the film's release on June 1 as many as 1 million viewers will see the ad.

The advertiser-funded nature of the service forms part of Channel 4's strategy to experiment with different models of making the delivery of online content cost-effective.

It is also possible to watch live streaming of action in the Big Brother house by signing up for a pass at £7.99 for the entire series.

Channel 4 has also given the website its biggest makeover in five years. Handled by digital agency Holler, the site also offers separate Big Brother's Little Brother and Big Brother's Big Mouth homepages for the first time.

There is also a new contestant bar designed to cope with the changing cast of housemates.

Big Brother 7 proved there's plenty of life left in the long-running reality format, opening last Thursday with 7 million viewers - the show's best ever opening night audience.

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