Guidance fleshing out plans to merge Britain's high-security hospitals with NHS trusts will do little to tackle 'entrenched problems' of recruitment, size and morale, according to mental health experts.

The government has already promised legislation to bring trusts and the high-security hospitals together.

An NHS Executive circular says this will mean mergers between high security services and trusts 'with experience of running medium-security services'.

Ashworth Hospital is already 'exploring an alliance' for partnership with Mental Health Services of Salford trust, from which its chief executive is seconded.

Rampton Hospital has signed a 'formal partnership' with Central Nottinghamshire Healthcare trust, while Broadmoor Hospital has identified two potential partners in the NHS.

But former Special Hospitals Service Authority chief executive Charles Kaye said 'the third set of major organisational changes within a decade' will not address 'more significant issues' dogging the service. He said that it was 'debatable' whether short-term secondments and job-sharing between trusts and high-security hospitals could address a 'long-term staffing crisis'.

The partnership arrangements reflected 'a view within the Department of Health that the special hospitals cannot be trusted to run themselves' following the Fallon inquiry into Ashworth's personality disorder unit, he said.

Former Broadmoor chief executive Alan Franey welcomed the closer integration as 'something I have been talking about for a very long time'. He said the key issue deserving attention was the size of the hospitals, and estimated a third of patients currently detained did not need a high-security setting.

Dr Matt Muijen, director of the Sainsbury Centre for Mental Health, said the moves towards integration were 'very good news'.

But he highlighted the 'very high demands on management' that joint organisations could impose.

The circular also outlines shadow arrangements for devolving the commissioning of mental health services from the High Security Psychiatric Services Commissioning Team to health authorities.

From April 2000 HAs will work with each other 'under the arrangements for specialised commissioning within their region' to commission the most secure services.

Commissioning in the New NHS: Specialised Commissioning - high and medium security psychiatric services.