Ministers will impose tighter controls on the BBC to halt its drift towards populism, according to an influential government adviser.

Writing in a pamphlet for left-wing think-tank Demos, Barry Cox -- chairman of the state-backed Digital Stakeholders Group -- predicted that the Department for Culture, Media and Sport would use the renewal of the BBC's charter in 2006 to introduce stricter public service obligations.

His forecasts will be especially worrying for BBC chiefs given Cox's connections. He is said to have the ear of both culture, media and sport secretary Tessa Jowell and prime minister Tony Blair.

The Corporation has been hoping to escape the kind of regulation imposed on digital youth channel BBC3. Ministers refused to sanction the station's launch until the broadcaster agreed to minimum levels of news, current affairs, arts and science programming.

However, according to Cox, this could be the shape of things to come. He argues that other BBC channels may have similar requirements thrust upon them when the government renews the charter that governs the broadcaster in two years' time.

"It is politically and administratively easy to introduce such a change, and is the most likely substantial reform to happen," Cox forecast.

Traditionally, the public service role of the BBC -- which is funded by the licence fee, a tax on TV-watching households -- has been less well defined than that of commercial rivals ITV and Channel 4.

Cox believes that under director general Greg Dyke -- with whom he once worked when at ITV station LWT -- the BBC has exploited this situation to chase ratings through populist shows.

"The longstanding defence of the relative freedom given to the BBC to interpret its public service obligations, as compared to the tougher regime applied to ITV and Channel 4, was that it could be trusted to honour the spirit of the charter," he declared.

"However, following the arrival of Greg Dyke as director general in 2000 and the more commercially aggressive strategies he encouraged, this became visibly less tenable."

As head of the DSG, Cox is charged with guiding Britain into the digital age. He is also deputy chairman of terrestrial station Channel 4 -- a broadcaster that would clearly benefit from stricter curbs on the BBC.

Cox has criticised the Corporation in the past, and on one occasion attacked its "cultural tyranny". He is known to favour funding through voluntary subscription rather than the licence fee, but admits that such a move is unlikely in the 2006 charter review.

Data sourced from: MediaGuardian.co.uk; additional content by WARC staff