The BBC has been accused of trying to bring in a 'two tier' licence fee after it was revealed the corporation is looking into a pay-per-view scheme for its vast archive.

Under the controversial plan, viewers would pay a small, but yet to be disclosed, charge if they wanted to watch a BBC programme from its huge back catalogue.

At the moment many favourites can be seen for free soon after broadcast via the online iPlayer service but for a limited period

The new scheme would let them see programmes at any time, either to watch once or, possibly, to download - though this, too, may turn out to be for a limited period.

According to trade journal Broadcast, insiders say the plan will not be for a profitable venture but one which charges to cover its costs. The service could cost millions to set up and operate, say industry experts.

A BBC spokesman admitted: 'Careful modelling will be required but it's something we're looking at.

'This is one of a series of ideas we are considering.'

Problems that need to be ironed out include what to pay independent production companies who own the content rights on many BBC shows made since 2003.

Then there is the conflict with the DVD/Blu-Ray sales of BBC series and how the service could affect profits.

To counter this, the pay per view service will not offer previews, interviews or any of the extras to be found on a typical series DVD or Blu-Ray box set.

The BBC spokesman added: 'We need to talk to the industry to ensure we are doing it in a way that works for everyone, so it is not imminent but it is something we are looking at.'

In previous interviews, BBC director general Mark Thompson compared the pay per view idea as like having a BBC library where 'shelves are cleared every seven days.'

The BBC is hoping to the system will be in place within three years and already established by the time its Charter is renewed in 2016.