Health Secretary Jeremy Hunt is preparing to order Kingston Council to slash nearly £650,000 from its budget for tackling obesity, teen pregnancy, smoking and other services.

Control of public health, including sexual health services, substance abuse treatment and suicide prevention, was transferred to councils from the NHS in 2013.

The Government has suggested it could cut £200m nationwide after a consultation with councils this month.

David Cameron pledged £8bn extra a year for the NHS following a pre-election plea by NHS England boss Simon Stevens – but Mr Hunt has said it must save billions more.

Kingston Council put on a brave face over the unexpected “blanket” cut.

Conservative Councillor Cathy Roberts, cabinet member for health, said: “The consultation, which closes on August 28, is likely to impact Kingston’s £10.4m ring-fenced public health grant.

“However, we will await the outcome of the consultation and do what we have to do to ensure public health in Kingston is addressed in a way that best serves our population.”

The Royal College of Nursing warned the proposed cuts, equivalent to 6.2 per cent of councils’ public health budgets, would disproportionately hurt London boroughs and worsen inequality.

Bernell Bussue, its London director, added: “It is no good claiming to protect the NHS budget, but then making huge cuts to local authority services, which are there to keep people well and out of hospital.

“The health service will in the long term end up paying for these savings many times over.”

Extra patients could cause even more problems for Kingston Hospital, which predicts an £8.8m deficit this year.

Neighbouring hospitals like St George’s are in even deeper financial trouble.

Grahame Snelling, chairman of Kingston Healthwatch, said: “We are very concerned about any impact there might be arising from these proposed savings.”

Public health services are of “critical importance”, he added.

But Dr Naz Jivani, chairman of Kingston clinical commissioning group (CCG), said: “Close working arrangements between the borough and the CCG will continue to deliver high-quality services.”

A Department of Health spokeswoman said: “The NHS budget will remain protected but difficult decisions need to be made right across Government to reduce the deficit.

“Local authorities have already set an excellent example of how more can be done for less to provide the best value for the taxpayer.”