Small companies in London are set to be hit with a business rates 'double whammy' that could force them to pay up to £500 extra tax.

Leaders of London councils yesterday urged Alistair Darling, the chancellor, to step in to prevent the rise at a time when small businesses were already struggling with the recession and credit crunch.

The rate rise is being caused by the result of a 5% increase to the figure used to calculate business rates and the ending of transitional relief.

Financial Times