Last week's somewhat astonishing comments by former Cabinet secretary Lord Turnbull on the Government's spending targets ought to ring warning bells for George Osborne.

The noble peer told the Lords economic affairs committee that Osborne's target of achieving a budget surplus by 2019/20 was merely a ‘smokescreen' for a smaller state. While the peer agreed austerity was necessary when the debt-to-GDP ratio was rising there was no need to aim for a surplus once the deficit was down, as indeed it is from about 11% in 2010 to 5% now. In other words, the Tories were reverting to type and using austerity to mask their traditional antipathy to public spending.