The Department of Health is braced for criticism today of its failure to mount a clear strategy to combat Britain's public health crisis in the crucial battlegrounds of smoking, obesity and diabetes.

Successive ministers in John Reid's department will be accused of overseeing too many overlapping and ineffectual agencies, of short-termism and of failing to establish proper machinery to judge whether specific government interventions to curb ill-health are cost efficient.

The criticism will come in an official report written by the former National Westminster Bank chairman, Derek Wanless, and submitted to the Treasury and the Health Department.

Mr Wanless has already delivered one report, championing a taxpayer-funded NHS as the fairest and most efficient model for health care.

Wanless II, published today, is expected to recommend that the Department of Health must be transformed from a sickness service to a sickness prevention service. The Wanless team will claim that:

· many of the department's public health targets are contradictory, inadequate or too blunt;

· targets to stop people smoking for as long as four weeks are pointless;

· investment in government smoking cessation services are inadequate.

· many previous public health campaigns have failed to reach people who are "lifestyle illiterate'.'

Mr Wanless will warn: "After many years of government policy and review, with little change on the ground, the key challenge now is delivery and implementation."

The health secretary and the chancellor are expected to welcome the report as a serious contribution to a vital debate. But privately some Whitehall officials predict that: "It may be a bit of a damp squib because it is less substantive than we had hoped in terms of producing a list of effective priorities."

The culture secretary, Tessa Jowell, will intervene today to highlight efforts to restore school sports. New figures will show that most change-of-use planning applications involving school playing fields include investment in sports facilities. Critics claim that school fields are being sold at an unprecedented rate - 1,325 applications to build on school grounds were received in the year 2002-03 alone.

To stimulate public awareness of the issues and options that Wanless has not fully grasped Mr Reid has already announced a white paper on public health to appear in July. He favours "informed choice" for consumers rather than compulsion. Both options are part of the "big conversation" with voters that Tony Blair launched last autumn.

Mr Wanless will assert that "the right of individuals to have their own lifestyles must be balanced against the adverse effect that choice has on the rights and behaviour of others".

Downing Street still favours locally imposed smoking bans. Officials also argue that letting local authorities take such decisions would strengthen the drive to decentralisation.

"If a lot of local authorities came on board and achieved critical mass it would be easier for government to come along behind as a sweeper and introduce legislation," one policy adviser said last night. How far that can be extended to local decisions on school sports and children's food is unclear.

Anti-smoking groups such as Ash regard the report as support in principle for a smoking ban. But sources throughout Whitehall admit that Mr Wanless refrains from any immediate policy recommendations, such as a public smoking bans, fat taxes or subsidies for users of gyms. He suggests that sub sidies for gyms might not be cost-effective since there is no guarantee that gym member will actually take exercise. He also says that it is too soon to judge the effectiveness of anti-smoking measures already taken by Labour, such as the advertising ban.

Public health campaign groups will seize on the report as the intellectual basis for a big switch in resources in the Department of Health and clearer interventions on smoking, diet and physical exercise.

The Wanless report will argue that excess rates of coronary disease, cancer and stroke among low income groups largely account for the differences in life expectancy and are linked to lifestyle.

He will point out that the government has published a plethora of green papers, but without establishing any clear system of measuring whether particular interventions are cost-efficient.

Faced with growing obesity and related illness the government must move away from short term budgets, short term initiatives and short term targets in favour of a 20-year approach, Mr Wanless will say.

He has warned that unless the public become fully engaged in their own health, the NHS might need to spend an extra £30bn by 2022.