Hundreds of foreign media groups including AFP on Tuesday accused Britain's Conservatives of undermining press freedom by imposing charges on journalists to cover their annual conference.

Prime Minister Rishi Sunak's ruling party first imposed a fee for media accreditation at last year's conference, defying complaints from both UK and foreign organisations.

It has again imposed charges for the October Conservative party conference in Manchester, northwest England, imposing a £137 ($175) charge, rising to £880 from August 1.

The Tories insist that the money raised helps to cover the administrative costs of "thousands" of journalists failing to show up.

But the Foreign Press Association of UK-based overseas media said the party had failed to show any evidence for no-shows on such a scale -- and argued that wider principles were at stake.

"In fact, this decision sets a dangerous precedent for countries all over the world who will use this decision to justify financial and other barriers to media scrutiny of the political process," it said.

"We therefore call upon the Tory party conference organisers to scrap or refund the charges and allow fair and free reporting for all."

The open letter was signed by nearly 300 media groups including Agence France-Presse, the New York Times, the Washington Post, Le Monde, The Hindu, Yomiuri Shimbun, Der Spiegel and the Sydney Morning Herald.

Media in more than 60 countries were represented, including from China and Russia.

Some UK media also complained about the introduction of the charges last year, but have yet to make a collective stand.

AFP contacted Conservative headquarters but there was no immediate comment.

Media access to the UK's main opposition Labour party is free up until July 28, then a charge of £75 is imposed until August 31, rising to £95 from September 1 onwards.

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