Sir David Nicholson has called for politicians to be “honest” about the “nature and scale” of service change required in the NHS because of the spending squeeze.

The NHS chief executive, also chief of the NHS Commissioning Board, was speaking at the NHS Confederation conference today.

He said the service had now to put reconfiguration plans “into action”, because continuing to make conventional efficiencies would put patients at risk.

He said the scandal at Mid Staffordshire Foundation Trust had shown the risks of that. Sir David said: “A drive for straightforward efficiencies in the system can put us in great danger.

“If we try to achieve it [savings] by constantly trying to make efficiencies we’ll put ourselves into a really dangerous place.

“No matter how brilliant our nursing staff are – and the vast majority really are – it is really difficult to give frail elderly people with dementia the care they need on an acute medical ward.

“The answer is about transforming services.”

However he said: “I do think politicians at all levels need to be straightforward about the need for radical change in the NHS. Without political support it is difficult to have the debate with the public.”

Sir David called for “national politicians” to be “honest with the public about the nature and scale of change that is needed”.

Speaking at the conference yesterday, health secretary Andrew Lansley said politicians should not tell the NHS what service change is needed, so he would not do so.

Meanwhile, Sir David said that, as well as CCGs, changes should be let by networks of clinicians formed at various levels, including clinical senates. The commissioning board yesterday published details of clinical senates.

Sir David also said the commissioning board wanted to develop a national strategy for redesigning services over the next decade to plan for funding staying static, growing demand and changing technology. He said the strategy would be used to decide changes to system “levers”, such as the tariff and use of capital.