Mervyn King has strayed well outside his usual monetary policy terrain, deep into fiscal policy. The governor of the Bank of England deliberately made an incursion in a set-piece parliamentary appearance. The strongly worded advice he gave to his elected masters underlines the depth of the UK’s economic plight. Politicians need to catch up with reality.

Mr King said that the Treasury should not increase discretionary spending further, unless it proposed specific, targeted measures. The UK economy is already on a drip-feed of potent monetary and fiscal stimulus – yet to take full effect. And with a fiscal deficit of above 10 per cent of output, the government cannot be blasé about further spending.