Unions gave warning last night that plans to make further Whitehall efficiency savings would lead to tens of thousands of job losses and damage public services.

The Chancellor announced last autumn that £30 billion should be found between 2008 and 2011 but yesterday he demanded an extra £5 billion in the same period.

The Treasury claims that more than 86,000 Whitehall jobs have already been lost during a rigorous exercise masterminded by Sir Peter Gershon, the efficiency guru, and has been careful not to put numbers on further job cuts. But the Public and Commercial Services Union said last night that there was no more fat to cut. Ten thousand more jobs were now being planned at the Ministry of Justice, 12,500 at Revenue & Customs and 10,000 at the Ministry of Defence.

Although benefit services would be under pressure with rising unemployment, the Department for Work and Pensions also expected 10,000 further job losses, the union said, adding that further job cuts and office closures in areas such as tax would damage public services.

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