The closure of six military barracks - two each in Kildare and Cork, one in Dublin and one in Monaghan - will be approved by the Cabinet today and formally announced later by the Minister for Defence, Mr Smith.
The radical cutbacks will involve the relocation of up to 900 members of the Defence Forces, but sources last night said that there would be no redundancies as a result of the closures.
Savings are expected to amount to £50 million, which will be reinvested in infrastructure and improving military equipment.
The properties, some of which are potentially extremely valuable, will be sold as soon as possible.
The installations due to be close are: Clancy Barracks at Islandbridge, Dublin; Castleblaney, Co Monaghan; Devoy Barracks, Naas, Co Kildare, which accommodates the Army apprentice school; Magee Barracks in Kildare town; Fitzgerald Camp, Fermoy, Co Cork; Murphy Barracks, Ballincollig, near Cork city.
There are 34 military installations in the State and the Minister for Defence and his officials are understood to take the view that this figure is too high. Too much time and money is spent just maintaining and securing the premises, sources said.
The Minister is expected to outline the case for closure to his Cabinet colleagues today before going to McKee Barracks on Dublin's northside to announce the decision. While objections to the closures are anticipated, particularly because of the economic impact on local communities, sources said the fact that no job losses were involved would allay grievances.
Military personnel affected by the changes will be moved to other installations and nobody is to lose rank or job status as a result of the developments.
In the case of Magee and Naas barracks, the 270 personnel will be moved to the Curragh, 12 miles away. Military personnel stationed at Ballincollig - over 140 in all - will be moved to Collins Barracks five miles away. The 130 stationed at Fermoy will also go to either Collins Barracks or Kilworth, which is located on the main Cork-Dublin road. The 80 military personnel at Castleblaney will be moved to Dundalk or Monaghan. Personnel stationed at Clancy Barracks at Islandbridge will either go one of the other Dublin barracks or to the Curragh. The apprentice school will be relocated.
The sale of Clancy Barracks is expected to deliver the largest yield to the Department of Defence, given its suitability for property development.