Proposals to increase NHS responsibility for prison healthcare could have 'high-cost implications' for the health service, prison reformers have warned.

Ministers are due to announce 'partnership' proposals for prison healthcare by the end of the month. There is speculation that finance is at the root of delays over reform.

A review led by former NHS Executive head of healthcare Graham Winyard and prison service head of healthcare Michael Longfield was due to report to ministers nine months ago.

HSJ sources say that under the proposals, the Prisons' Board and the NHS Executive would become jointly accountable for healthcare in prisons. A taskforce of prison area managers and NHS regional office staff would monitor the delivery of services towards targets likely to be agreed between health authorities and prisons.

Prison funding for health - currently part of the general allocation for prison services - would be ringfenced.

The proposals will also aim to find a more consistent approach to the way contracts are set up between prisons and trusts.

But the review has backed away from plans that would have given the NHS full responsibility for prison healthcare.

Director of the Prison Reform Trust Stephen Shaw said the proposals 'implied a significant increase in resources' for the NHS. Despite warning that 'the devil is in the detail', he urged health ministers to 'bite the bullet on this one' and implement the proposals in full.

But Frances Crook, director of the Howard League for Penal Reform, said the impact of change was likely to be cultural rather than financial. She said closer working with the NHS could create 'a cultural and ideological shift' away from a system under which staff saw themselves as 'prison officers primarily and health professionals second'.

Ms Crook added: 'That is the reason why organisations like ours want prison services to become part of the wider community of health - not because we think it will mean more resources.'

The review was sparked by a report by the chief inspector of prisons, Sir David Ramsbotham, in 1996. It urged full integration of the prison healthcare service with the NHS.

Brian Caton, assistant secretary and head of health at the Prison Officers Association, said full integration was 'not possible, not practical and would be dangerous'.