Plans to overhaul the 1983 Mental Health Act may not be realised until after the next general election, key mental health groups say.

A Department of Health spokesperson agreed this week that this was 'a pretty accurate assessment'. But the promise of a new act has prompted commentators to warn that battles over the contents of legislation might 'distract us from the real agenda of service implementation'.

Health secretary Frank Dobson set out his intention to change the law in a letter two weeks ago to Professor Graham Thornicroft, who chairs the reference group drawing up a national service framework for mental health.

He said the legal review could cover 'compliance orders and community treatment orders' to form a legal basis for dealing with patients who stopped taking their medication or whose condition deteriorated.

But the DoH spokesperson said it might not be possible to set a schedule until the reference group issued its report.

He also said the review could not begin until experts had carried out a 'scoping study'.

A spokesperson for Mind said: 'It is unlikely that there will be time in this parliament. Certainly there has been no indication that it is a priority.' A similar assessment was made by the National Schizophrenia Fellowship.

Mental health groups say the 'root and branch' review promised by Mr Dobson would take at least 18 months, and should be followed by a green paper consultation and a white paper.

This would leave time to insert legislation in the final Queen's speech of the present parliament. But governments often prefer to avoid controversial legislation so near an election.

NSF chief executive Cliff Prior welcomed the idea that legislation may take some time. 'We are pleased attention is being given to getting services right first before trying to fix the law - the law is no substitute for effective services.'

But Matt Muijen, director of the Sainsbury Centre for Mental Health, warned: 'Battles over the Mental Health Act might distract us from the real agenda of service implementation.'

Professor Thornicroft's group has already set up eight specialist sub- groups (see box).

Mr Dobson is due to make a statement to the Commons in October about funding its proposals. A sum of 1bn over five years has been suggested. The group will produce its final report in January for possible publication in March.

Service framework sub-groups

Population-level needs assessment and commissioning.

Mental health promotion, access, referral, transfer, discharge, primary care and definitions of severity.

Initial assessment, early intervention, crisis intervention, accident and emergency and 'place of safety' services.

Longer-term treatment and care in hospital and the community.

Treatment and care outcomes at service-user level (including audit and research).

Monitoring service-level inputs, processes and outcomes, and performance management.

Organisation and management of mental health treatment and care services.

Workforce, education and training.