The Government's 50% bank bonus tax has already raised £2 billion for the UK public purse, the Chancellor revealed today.

Alistair Darling said the windfall tax - introduced on bank bonuses above £25,000 - had raised far more than the £550 million originally expected.

He reiterated support for a global levy on the banking sector, but said the UK should not go it alone in introducing a new bank tax.

In pledging to recover money forked out by taxpayers to help the banking sector, Mr Darling added that more than £8 billion in fees and charges had been received from banks in return for support during the financial crisis.