Key figures in local government have raised concerns about delivering efficiency savings through regional procurement of social care services.

The new president of the Association of Directors of Social Services, Tony Hunter, told delegates that the target came at a time of rising costs in the care home and home care sectors and greater pressure to offer choice and increase uptake of direct payments.

He said: "We must never close our minds to the possibilities, but the simple truth is that there are no bulging back pockets, either potential or undeclared, in the local government world I know, and the realities of funding pressures must be faced."

Sir Peter Gershon suggested in July that 35 per cent of the £6.45bn efficiency savings local government will be responsible for delivering by 2007-8 could be made through the changes in procurement methods.

However, Hunter doubted that such a simple solution could be found to a problem so complex.

Alison King, chair of the Local Government Association's children and young people board, echoed calls for greater clarity.

She said: "We need to be an awful lot clearer about what precisely efficiency savings mean in this context and the particular contribution that commissioning can make.

"It is already evident that 'better commissioning' is often about redirecting resources more effectively and not necessarily saving money."