LONDON (Reuters) – A planned tax on financial transactions in 11 euro zone countries would cut the value of household savings in non-participating Britain by 4.4 billion euros (3 billion pounds), a report for the UK financial sector said on Tuesday.

Britain, the European Union’s biggest financial centre, fears that many trades executed in London will be hit by the tax and is challenging it in the European Union’s top court.

The report from London Economics, a policy and economics consultancy, said the impact would come from the practically instantaneous effect of the tax on the value of household stock and bond holdings.

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