It was billed as the first television show designed for the social networking generation. But not even Lily Allen could rescue the BBC’s latest attempt to lure the “youth” market.

Lily Allen and Friends, the flagship show in a relaunch of BBC Three, the controversial £83 million channel aimed at 16-34 year olds, attracted just 255,000 viewers.

Fronted by the pop singer, who launched her career through MySpace, the BBC promised a new form of chat show featuring web celebrities and questions set by Allen’s “web friends”.

But it was claimed that a third of the studio audience walked out because they were bored while web users said the programme looked like a desparate BBC attempt to appear “trendy”.

Guest star David Mitchell, the comedy actor, looked uncomfortable when he was forced to watch web clips of animals having sex.

Despite a prominent marketing campaign, Lily Allen and Friends attracted just 2 per cent of the multichannel audience on Tuesday night.

The audience slumped from the 861,00 viewers who watched the preceding programme, a repeat of EastEnders, to 247,000 when the chat show had finished.

Lily Allen reduced BBC Three’s average audience for the 10:30pm slot by some 200,000 viewers. The E4 channel attracted a higher share of the target youth audience during the evening. ITV2 attracted more viewers than Allen with an Arnold Schwarzenegger film.

The figures will raise further questions about BBC Three, which has the highest cost-per-programme of any corporation channel, despite a small audience. John Humphrys said the BBC should close the channel, five years old this month, rather than cut the news and current affairs budget.

But Allen, 22, defended the show. She wrote in her MySpace blog: “The audience were great, standing in a hot studio for two hours watching me fluff my lines is not my idea of fun, but they seemed to enjoy it.

“Due to it being the first show we’ve done, we ran over a little and naturally a small number of the audience had to catch the last trains back to wherever they came from.”

The BBC said many more viewers would have watched the Lily Allen show when it was simulcast through the BBC website or on the iPlayer catch-up service.

Critics praised another new BBC Three addition - Phoo Action, a kung-fu action drama based on comic characters created by Jamie Hewlett, a member of animated pop group Gorillaz.

Danny Cohen, BBC Three Controller, said: “We’re trying lots and lots of youthful new things on BBC Three - from new entertainment talent to bold and innovative British drama.

“I’m hugely encouraged by the quality and initial impact of all of our changes, and am looking forward to growing our young audiences further.”

The BBC said the audience share for BBC Three this year among 16-34s was 3.8 per cent, 32 per cent on the same period last year.

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