THE government minister in charge of stamping out corporate tax avoidance has himself set up a business in the tax haven of Bermuda. Lord Myners, already under fire for approving Sir Fred Goodwin’s massive pension from Royal Bank of Scotland (RBS), was part-time chairman of an offshore company which avoided more than £100m a year in taxes.

Details of Myners’s involvement in Aspen Insurance Holdings (AIH) have emerged as Gordon Brown seeks to win the backing of heads of government to prise open tax havens at a meeting of the G20 in London on April 2.

Myners, who earned nearly £200,000 from AIH in one year, is also facing questions over share options he accrued during five years as chairman of the Bermuda-based company. Accounts for AIH show that at the end of 2007 Myners held 318,338 share options. On Friday the shares, which are listed on the New York Stock Exchange, closed at $21.64, which would value that stake at £4.8m.

Myners, financial services secretary to the Treasury and former chairman of the Guardian Media Group, was awarded the majority of the share options at an exercise price of $16.20 a share in August 2003, a year after he helped to start the company.

When he stepped down in May 2007 he was given until August 2008 to buy the shares. If he had bought the shares between January and August last year, when Aspen’s share price fluctuated between $22.59 and $29.90, he would have made a profit of between £1m and £2.1m.

When approached by The Sunday Times on Friday morning, Myners declined to say whether he had exercised the shares. On Saturday afternoon a Treasury spokesman said that Myners had not exercised the share options and owned no stock in Aspen.

Although any share transactions made by Myners while he was a director would have had to have been declared, these rules cease to apply once a director leaves the board.

A filing with the US Securities and Exchange Commission discloses that Myners, who is also leading the government’s clampdown on City bonuses, received a farewell bonus of £50,000 for his final four months at Aspen. The company specialises in property and crisis reinsurance policies which pay out in the event of hurricanes, floods and other natural disasters.

His five-year term as chairman of both the UK and Bermuda arms of Aspen ended in May 2007 and he became a minister last October.

Reinsurance companies that set up in Bermuda do not pay tax on the premiums they raise in the UK. These revenues are transferred to Bermuda, where they are invested tax-free. Companies based on the island also escape corporation tax. Although Aspen has offices and most of its staff in London, its parent company is based in Bermuda.

Aspen’s parent company made profits of $489m (£349.2m) in 2007. Had AIH been domiciled in Britain it would have had to pay £104m in corporation tax. Several subsidiaries do, however, pay tax in the UK.

Richard Murphy , an adviser to the Tax Justice Network, which campaigns against tax havens, said: “The reason insurance and reinsurance set up in Bermuda is to avoid tax.

“Now we find that the man charged with getting City institutions to pay all their tax is in fact an expert in how to avoid tax. The government has put a fox in charge of the chicken coop.”

The US Congress has named Bermuda as one of more than 30 “offshore secrecy jurisdictions” in legislation to crack down on havens in the coming weeks.

Brown has repeatedly called for tax havens to be outlawed. In December Myners helped to launch a government investigation into the tax lost through havens, saying: “Off-shore financial centres must play a responsible role in the global financial system.”

The Treasury said he had complied fully with the House of Lords reporting rules for financial interests. A Treasury spokesman said: “Lord Myners has no continuing interest in or income from the company. [He] is fully domiciled in the UK for tax purposes; all previous income and capital gains [he] made from the company were taxed in the UK at the usual rate.”

Myners also faces a challenge to his account to the Treasury select committee last week in which he said he did not know the full cost of Goodwin’s RBS pension.

Sir Tom McKillop, the former chairman of RBS, has written to John McFall, the committee’s chairman, insisting that Myners was told the full value of Goodwin’s £703,000-a-year pension.

Michael Fallon, deputy chairman of the committee, said: “If the letter contradicts what Lord Myners told the committee then it could be very serious for him.”

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