The most radical reorganisation of hospital services for decades is to be announced today by Health Minister James Reilly.

Minister Reilly will publish a report on the establishment of new hospital groups, which will eventually become hospital trusts, along with a report on the future role of smaller hospitals.

The publication of the reports has been delayed for some time.

It is expected that hospitals will be reorganised into six groups, which, under Dr Reilly's reform plans, will eventually become self-governing trusts. There will be close cooperation and sharing of services between hospitals in the groups.

Major emergency and acute services will move from smaller hospitals to larger centres, but the smaller hospitals will take on new roles.

Many of the smaller hospital units, such as Roscommon, Nenagh,Ennis and Dundalk, have already had their major acute services transferred to large centres. The new report will provide for the transfer of these services from other small hospitals such as St Columcille's in Loughlinstown.

The safety body HIQA has expressed concern about the continuation of major acute services in smaller hospitals on safety and quality grounds.

It is expected that the report will provide for the establishment of six hospital groups.

The groups will be organised around four major hospitals - St James's, Beaumont, Cork University Hospital and University Hospital Galway, with major roles too for the Mater and Tallaght in Dublin, the Mid-Western Regional in Limerick and Waterford Regional.

Hospitals have already been organised into groups in the west and north-east and of the country.

Concerns over the future status of Waterford Regional Hospital as a result of the organisation are believed to be addressed in the report in terms of specialties it is to retain and new academic links for specialist posts. Waterford is to be linked with other hospitals in the south in Cork, Kerry and South Tipperary.

Ireland has traditionally a much more fragmented hospital service than many other developed countries, with a proportionately higher number of small hositals providing major servivces than in other health systems.

Plans to to reorganise our hospital services and to transfer major services from smaller centres date back to the 1930s, but the first reorganisation plan in recent decades was the Fitzgerald Report in the late 1960s.

These plans have until recent years usually been stymied by political and local opposition.

However safety concerns and resource issues have recently helped progress the transfer of services from smaller to large hospital centres, although these moves have still met with strong local opposition.