Talks between nursing unions and health service employers on claims for improved pay and conditions have ended without agreement.
The Irish Nurses Organisation and the Psychiatric Nurses Association have said a work to rule by nurses will commence in hospitals at 8am tomorrow morning.
The talks related to claims by up to 40,000 nurses and midwives for a 10% increase in pay and a 35-hour working week.
The Minister for Health, Mary Harney, said the industrial action being embarked on was unnecessary and would have serious implications for patients as well as causing unnecessary anxiety for their families.
She called on the unions to reflect on their position and to use in full the industrial mechanisms of the state to pursue their claims.
The Health Service Executive has said the industrial action by nurses will cause significant disruption to hospital and community-based services.
In a statement, the HSE accused nurses of planning to withdraw from core nursing functions, such as using IT systems in Accident and Emergency units.
