Britain turned down the chance to mount a £100m tax crackdown on residents with funds parked in Liechtenstein two years ago because the UK’s tax authority did not want to pay a whistleblower. The informant instead turned to Germany’s secret service, selling a list of at least 750 names of Germans with money stashed away in Liechtenstein and sparking Berlin’s biggest crackdown on tax evaders.

Germany’s huge success with the secret list – bought for €4.2m ($6.2m, £3.1m) in January 2006 – finally persuaded the British authorities to hand over £100,000 to the whistleblower, believed to be a former employee of Liechtenstein’s LGT bank.