It will be February 2032 before Britain’s debt burden falls back to the level that would have been required to meet Gordon Brown’s once-cherished “golden rule”, according to an analysis of Wednesday’s Budget by the Institute for Fiscal Studies.

Britain faces “two parliaments of pain” in which borrowing will be so substantial that it will be more than 20 years before debt falls back to the 40 per cent of national income that the prime minister identified as the maximum acceptable during his tenure as chancellor.