Alistair Darling on Wednesday rejected business pleas for a delay in implementing his contentious tax clampdown on non-domiciled foreigners living in the UK.

The chancellor is facing increasing pressure for a postponement, following his partial retreat on the issue this week. Experts argue that the sheer complexity of the changes, allied to the lack of certainty over their precise effect, mean more time is needed for consultation to avoid the new tax package damaging the City.