Hermitage Capital, whose manager William Browder has been barred from Russia for more than two years, alleged yesterday that it and HSBC bank had been victims of an elaborate attempt in Russia to defraud them of hundreds of millions of dollars.

A legal complaint to Russian prosecutors sent by lawyers representing Hermitage and HSBC Management Ltd in Guernsey, which is trustee and manager of the Hermitage fund, said the company's Russian assets had been the target of a "large-scale criminal conspiracy".