An extra £5bn in efficiency is to be achieved in the current Comprehensive Spending Review period, Alistair Darling has announced in the Pre-Budget Report.

The chancellor said the extra savings would be added to the £30bn announced in the 2007 spending review and would not jeopardise public service provision.

Darling also said the efficiency targets set by Sir Peter Gershon in 2004 had been surpassed by £5bn, reaching £26.5bn.

"Having carefully considered the extent and the limits of efficiency savings, today I can announce the government will now find an additional £5bn of efficiencies in 2010/11 for a total saving of £35bn over three years," the chancellor said.

Referring to the operational efficiency review currently being undertaken by external reviewers on behalf of the Treasury, he said: "We know extra savings are achievable because independent reviewers have identified new efficiencies across public sector operations."

"The efficiencies will come through lowering the cost of back office operations, better procurement, examining property holdings and asset sales."

"By continuing to make efficiency savings, we can help fund the action needed to help families and businesses."

The operational efficiency reviewers are due to report ahead of the next full Budget in March.

Speaking at the weekend, Chief Secretary to the Treasury Yvette Cooper said improved public sector efficiency was necessary to help mitigate the effects of increased pblic sector borrowing.

"At a time when families across the country are feeling the pressure because of the global credit crunch, they want be assured that the public sector too is doing its bit, and cutting out waste to free up resources that can support national priorities," she explained.

Reacting to the new proposed savings, Public and Commercial Services Union (PCS) general secretary Mark Serwotka said the £5bn should not come at the cost of civil service jobs.

"Further efficiency savings of £5bn should not be a prelude to yet more job cuts, office closures and privatisation. Key public services, such as justice, welfare and tax are already struggling to cope against a backdrop of massive job cuts and office closures."