Proposals to allow shire counties and the Greater London Authority to tax businesses to fund local projects will cost retailers £100 million.

The plans was revealed by Chancellor Alistair Darling in today's pre-Budget statement.

British Retail Consortium head of tax policy Ed Cooke said: “The British Retail Consortium believes such a tax is open to widespread abuse.”

He added: “Retailers already contribute more than£4.5 billion to the public purse each year through business rates alone. If every county across the country, including the GLA, were to use this power, more than£100 million in extra tax would be picked from retailers’ pockets every year.”