The proposed transition to a reformed health service will lead to “very real” risks, the NHS Confederation has said.

In its response to the Liberating the NHS white paper, the NHS Confederation said its members – 95 per cent of NHS organisations – support the government’s objectives in the white paper.

However, it said that the reforms would be challenging even in a benign climate. Considering the risks from the “hostile” financial environment the NHS is about to enter the Confederation said the transition would be “exceptionally difficult”.

Acting chief executive Nigel Edwards said ministers needed to ease worries about the transition, plans for which looked “bolted on”. “The risks are very real indeed,” he said.

The Confederation’s response said that contrary to the assumption implicit in the white pape,r markets would not be adequate to manage the system.

It questioned whether choice “is a powerful enough mechanism to create the level of change that is required, particularly given the limitations of the power of choice in more rural areas compared with urban ones”.

The response asked for clarification on the failure regime for trusts and requested an “urgent review” of the functions currently carried out by primary care trust and strategic health authorities, some of which the health secretary Andrew Lansley has said will be discontinued when the organisations are abolished.

The Confederation also warned debate about reform “should not take place against a backdrop of anti-managerial rhetoric,” adding that commissioning could be left “under managed” by the proposed 45 per cent cut in management costs.

On foundation trusts, the Confederation said the tactic of setting a date for all trusts to reach the status had been tried before and nothing had yet been done to remove the barriers to that failing in the past.

On GP commissioners, Mr Edwards warned that GP consortia could become the new “fall-guy” in the health service, taking the flack for failures. He said: “The lesson of PCTs is ‘that’s what that level in the system is for’”.

He also called for more clarity over how GP consortia will be accountable and the role health and wellbeing boards.

He said: “The fact of the matter is that the government is planning to build a very big new machine - at great pace - but no one can be quite sure what will happen when it is switched on.”