An alliance of British media organisations is calling on the BBC Trust to reject plans to run ads on the corporation's international websites.

The British Interactive Publishers Alliance is calling on the BBC Trust not to be tempted to approve the plan to run ads on the BBC's international websites as a "superficially attractive" way to "augment the licence fee", when it meets to discuss the project next Wednesday.

The group - which counts News International, Sky Interactive, the Guardian, Trinity Mirror and the Telegraph Group among its members - is calling on the BBC Trust to reject the proposal as it could kill the digital revenue creation plans of UK publishers.

"As well as undermining the corporation's worldwide reputation for integrity and impartiality, there would be a serious negative impact on all UK publishers, most of whom depend on the growing online advertising market for their revenue models," said Hugo Drayton, chairman of BIPA. "Furthermore ... this would be a first step on an inexorable route to advertising on the BBC's publicly funded sites."

BIPA argues that if the proposal is accepted it is "unrealistic" to believe in a future clear separation between the BBC's public and commercial output.

"To permit advertising on any part of the BBC's internet world will lead to a mixed-funding model, which has failed to maintain fair competition between private and public broadcasters in other European countries where this model prevails," said BIPA in a statement.

"BIPA has already raised concerns with the European Commission and will participate fully in their investigations into state aid for publicly funded broadcasters later this year, when competition aspects of new media will receive special attention."

In addition, BIPA points out that, as the sites are a commercial service, the BBC is not going through tests for public value and market impact - which questions the integrity of the new regulatory system.

"Because this is a commercial service the much trumpeted new public-value test will not be required," said Mr Drayton. "However, a loophole means that publicly funded BBC outlets trailing content on BBC.com will be permitted because the content is 'public service content' carried by a commercial delivery system.

"The BBC already enjoys substantial advantages from cross-subsidy and the cross-promotion of its internet activities from its broad range of TV, radio and magazine properties."

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