GORDON BROWN wants to recoup millions of pounds from celebrities as part of a Treasury drive to reclaim an estimated £97 billion underpaid in tax each year.

HM Revenue & Customs is mounting a test case against Richard Madeley and Judy Finnigan, the chat show hosts, that will set a legal precedent for television presenters, authors and footballers.

It claims that they have wrongly written off the cost of employing agents against their tax bills and wants to recover a six-figure sum to cover the period back to the late 1990s.

It could affect thousands of big names such as J K Rowling, the author, Jamie Oliver, the television chef, and Frank Lampard and Michael Owen, the England footballers, according to tax experts. In total the Revenue is hoping to recover hundreds of millions of pounds.

Legal and financial advisers to the celebrities maintain that they are acting entirely properly and that the Revenue is aggressively reinterpreting established tax laws.

Those potentially affected lashed out at the Revenue yesterday. Margaret Drabble, the author, described its action as “disgraceful”. She gives 10% of all her earnings to Michael Sissons, her agent of 40 years.

“I think it’s shocking, I can’t believe it,” she said. “The self-employed are the most vulnerable with regard to tax anyway, so this will be a terrible blow. I cannot exist without my agent, my entire life is run through him.”

Jilly Cooper, the author, said: “It seems incredibly mean. Agents are the lifeblood of authors. I don’t know what I’d do without mine, she deserves every penny she gets.”

Musicians, actors and dancers will be excluded from the clampdown under legislation which acknowledges their need to employ agents.

The Treasury hopes that the high-profile investigation will act as a deterrent.

Research by the Revenue has uncovered a multibillion-pound “tax gap” — the extra sum which could be collected if the chancellor closed tax avoidance loopholes and stopped illegal evasion.

The official analysis, which has not been published and is still not complete, is understood to have estimated that the “tax gap” accounts for at least 8% of GDP and could be as high as 12% — £97 billion to £150 billion. The figure has been calculated on the basis of representative audits of tax returns.

Much of the “missing tax” is from money held by British citizens and companies in offshore tax havens and not declared to the tax authorities.

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