Mr Osborne claims that he will claw back the money, and more besides, through new anti-avoidance measures.

ECONOMIST: Britain's budget

The government has now announced anti-avoidance measures targeted at this bed and breakfasting, as well as other more complex loan related planning arrangements.

BBC: Budget 2013: National Insurance, the Cinderella tax

This tax blueprint, first reported in the Financial Times, includes tough anti-avoidance measures that would catch some trades executed in New York, London, or Hong Kong -- even when no eurozone entity is buying or selling the product.

CNN: US banks warn over planned EU 'Tobin tax'