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THE taxman plans to bring to book the drug barons and City fraudsters who have squirreled away millions of pounds in secret Swiss bank accounts.

HM Revenue & Customs (HMRC) is linking up with the German tax authorities to get information about those who have deposited their ill-gotten gains amidst the snow-dusted mountain chalets.

The new access could even help recoup some of the money Britain is losing to Switzerland as it undercuts our tax rates to lure UK companies and the so-called “nondoms” – rich foreigners.

The taxman’s first targets are likely to include Curtis “Cocky” Warren, 44, once Britain’s most notorious cocaine trafficker, and the white-collar criminals behind so-called Vat “carousel frauds” that have cost the British government up to £4 billion a year.

Warren, a notorious drug smuggler, was released from a Dutch prison last year after serving 10 years for a £125m drugs plot and kicking a fellow prisoner to death. Only £3.6m of the money has so far been recovered.

Graham Johnson, author of The Devil, about Warren’s former empire, said: “His fortune is thought to be as much as £200m invested both in property and Swiss bank accounts, some of them in the names of other people.”

Swiss bank accounts have been shrouded in secrecy since medieval times, a privacy which was established in law in 1934. But HMRC plans to take advantage of a new tax treaty forged between Germany, Britain’s EU partner, and Switzerland. The treaty allows “mutual assistance” and says that the traditional right to secrecy does not prevent the procurement of documents as evidence in cases of fraudulent behaviour punishable by impris-onment.

Clive Gawthorpe, partner at the accountants UHY Hacker Young, said: “If the Revenue can use the Germans as a back door into Switzerland, that is a major coup in their battle against tax evasion from offshore bank accounts.”

Tax experts say Switzerland, which is home to an estimated one-third of offshore funds worldwide, has become more willing to cooperate rather than be tarred as a haven for terrorists and drug smugglers.

Last month Switzerland and Japan agreed to share £29m forfeited from the frozen Swiss bank accounts of a Japanese yakuza gangster, and a Swiss banker was arrested in a luxury hotel in Rio de Janeiro for allegedly helping wealthy Brazilians to evade tax.

Some accountants fear that the move could be widened to enable HMRC to pursue people who have legitimately moved to Switzerland, to check that their remaining UK assets are being taxed properly. However, HMRC would be barred from “fishing” for information and would need to supply names and allegations.

Typically, someone moving to Switzerland strikes a deal with the authorities to pay a levy based not on their earnings but on a formula that charges a minimum of five times the rental value of their property.

Lewis Hamilton, the racing driver who moved to Switzerland last year, could legitimately save almost £4m a year from his move. A senior official at HMRC said: “Our reading of the law is quite clear. Germany has the agreement with the Swiss, and we have an agreement with the Germans . . . Until now we have not had the opportunity to get at the Swiss assets of British tax dodgers.”

Last year HMRC netted at least £1 billion from an amnesty which allowed tax evaders to confess to the existence of their offshore accounts. More than 45,000 of them came forward.

Earlier this year, HMRC paid £100,000 for a list of suspected British tax dodgers in Liech-tenstein. It expects to recoup approximately £100m, but a trawl of Swiss bank accounts could be far more rewarding.

Mike Warburton of accountants Grant Thornton said: “It doesn’t surprise me at all that the taxman wants to piggy back off the Germans.

“Switzerland is not as safe as it was. Dubai and Singapore are about the only places left who have made it abundantly clear that they are not going to divulge information.”

John Whiting, of the accountants Price Waterhouse Coopers, said: “European tax authorities are getting into a club to exchange information. Bringing Switzerland into the fold is a key breakthrough.

“Nondoms are concerned that they might be investigated more but the taxman wants to catch evaders, not avoiders.”

Philip Beresford, who compiles The Sunday Times Rich List, said: “This will cause fear in the less powerful tax havens such as the Channel Isles and the Isle of Man.

“If Switzerland, the biggest and the strongest, caves in so easily, what hope do they have? In hedge fund alley in Mayfair, they’ll be asking: ‘Where do we hide it now?’”

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