BBC programmes will be made available to watch via the internet for seven days after their original transmission, as part of a service aimed at revolutionising viewing and listening.

The plans are expected to be matched by ITV today when it relaunches its own website, as broadcasters prepare to hasten the demise of the traditional television channel in favour of viewing on demand.

However, the BBC has been banned from offering free out-of-copyright classical music and audiobooks amid fears that it would harm commercial sales – to the frustration of Mark Thompson, the Director-General.

Yesterday, the BBC Trust, the corporation’s regulator, concluded that the plans for the catchup television service would create “significant public value with limited market impact”, as it formally gave the go-ahead for the service.

BBC programmes will be available via the corporation’s iPlayer internet service by, it hopes, the summer, and also on cable television, although the eight months it has taken to obtain regulatory approval will leave the BBC trailing commercial rivals.

ITV is expected to offer a rival service within weeks, and Channel 4 has been making catchup programming available on the internet and cable since December. Already 20 million programmes and other pieces of content have been viewed, demonstrating that viewers are no longer willing to be tied to the broadcast schedules.

The trust, though, said that it could not allow the BBC to replicate its giveaway of Beethoven’s works, because the regulator was “mindful that the market for classical recordings is in a precarious state”. It barred the BBC from releasing classical music without copyright protection, even though two thirds of listeners consulted said that the BBC should be allowed to do so.

An alternative proposal allowing the BBC to offer “taster pieces of classical music no longer than ten minutes in duration” was blocked, and the regulator said that it would not be acceptable for the BBC to add copy-protection to audio downloads.

Mr Thompson said, on behalf of the BBC’s management, that “we disagree with the trust’s decision to exclude classical music podcasts. Our research suggests that classical music audiences would wish to download classical music programmes from the BBC and to listen to them on their terms, free at the point of use.”

The BBC is investing £131 million in the technology over five years, although the service will initially be available only via Microsoft PCs using Microsoft software for technological reasons. But, to avoid criticisms that the BBC is favouring Microsoft, Mr Thompson was told that he must also try to develop software with other technology suppliers, including Apple, and be answerable for progress every six months. BBC television, although not BBC radio, will use copy-protection or digital rights management software to maintain time-based restrictions on viewing. Programmes downloaded will be available for only 30 days, to ensure that DVD sales are not damaged.

There will also be restrictions on the number of complete series that will be available for viewing on the internet or on cable. Only current series with a “narrative arc”, such as Doctor Who, will be available to download in a single block, and complete series can amount to only 15 per cent of the total amount of BBC content available. Top Gear, where there is no unifying narrative thread, will be not be available to download in a single block.

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