David Cameron has been handed another thinly-veiled rebuke by the statistics watchdog for claiming that Britain has been "paying down its debts".

Labour lodged a complaint about the Prime Minister's loose use of language after he used his conference speech to hail progress in turning round UK finances.

"Look what we are showing the world," Mr Cameron said. "Not just a country that is paying down its debts, and going from the deepest recession since the war to the fastest-growing major advanced economy in the world, but at the same time: a country that has kept its promises to the poorest in the world..." However, the chairman of the UK Statistics Authority, Sir Andrew Dilnot, said while the deficit has fallen since the coalition came to power in 2010, debt has risen. Sir Andrew noted that he had to issue a similar clarification in February 2013 after Mr Cameron remarked in a party political broadcast that the Government was "paying down Britain's debts".

In a letter to shadow chief secretary to the Treasury Chris Leslie, he said: "It is important... to understand the relevant statistical definitions and to distinguish changes in the level of debt outstanding from changes in borrowing per period."