Taxpayers face six years of austerity, paying for the consequences of recession and a £20bn fiscal stimulus unveiled on Monday by Alistair Darling as he detailed the most dismal Budget outlook seen since 1993.

National insurance contributions for both employees and employers will rise by 0.5 per cent. Those earning more than £100,000 will pay more income tax – with those on £150,000 facing a new higher tax rate of 45 per cent – and public spending faces its biggest squeeze for 15 years – although all these measures will not kick in until 2011, well after the next election. The tax clawback would leave someone earning £150,000 paying an extra £3,040 in tax.