BBC draws up plans to launch channels 3 and 4

The BBC plans two new channels in the biggest shake-up in its 25-year history. If its proposals are accepted, BBC3 and BBC4 would cater for youth and highbrow cultural markets respectively, as the corporation struggles to keep up with the rapidly developing world of multi-channel cable and satellite broadcasting.

The BBC plans two new channels in the biggest shake-up in its 25-year history. If its proposals are accepted, BBC3 and BBC4 would cater for youth and highbrow cultural markets respectively, as the corporation struggles to keep up with the rapidly developing world of multi-channel cable and satellite broadcasting.

BBC4 would aim to emulate the best in Radio 4 showing, for example, serious discussion programmes on science, politics and the arts, as well as top-rated orchestral music and drama. The new channel, which is likely to cost in the region of £50m a year, would be a key plank in the corporation's defence against charges that it is dumbing down.

BBC3, meanwhile, would aim at a younger, "cooler" audience offering something like the feel of MTV, the international pop channel, with the schedules dominated by 15- minute bursts of usually off-beat programming.

The plans will be announced later this month when the new direcor general, Greg Dyke, sets out his vision at the Mactaggart Television Festival held in Edinburgh.

But he can expect to run into controversy as under his leadership the corporation has already proposed far-reaching changes without any external consultation. These include proposals that BBC1 and 2 should become "genre" based channels, with BBC1 focusing on enertainment and popular programming while BBC2 tackles serious subjects.

There remains some doubt as to how far such changes can be made without explicit government approval. Chris Smith, the Secretary of State for Culture, has already warned Mr Dyke that a BBC1 channel devoted entirely to entertainment would be unacceptable.

The corporation is furthest down the line with its plans for a BBC youth channel, which already has a provisional budget of more than £90m.

For the past several months the corporation has been trying to turn its digital channel, BBC Choice, now seen as an expensive failure, into one it could relaunch as BBC3. The channel started life as an attempt to focus on the broader context behind the existing schedules, giving, for example, behind-the-scenes views of BBC dramas, and longer editions of Tomorrow's World. But these were judged to look too much like the existing terrestrial output, and late last year, the channel was given a dramatic change of direction.

BBC Choice now appeals to a younger market, with schedules featuring entertainment, that often has an ironic or offbeat twist, such as Christine Hamilton's chat show.