The main purpose of Lord Hutton's review of public-sector pensions in the UK, which published its interim conclusions yesterday, is to get the costs of unfunded schemes under control. Yet, one reform he is considering may actually make the bills appear bigger.

Hutton believes that the UK Government is currently underestimating the costs of the four unfunded public-sector schemes - those for the NHS, teachers, the civil service and the armed forces. According to the Government's figures the combined liability for these is around £835bn, but the Institute for Economic Affairs, and others, have put it at closer to £1.2 trillion.