The Health Service Executive Employers' Agency has said industrial action by the Irish Nurses' Organisation (INO) and the Psychiatric Nurses' Association (PNA) is damaging the reputation of nursing in Ireland.
Brendan Mulligan, assistant chief executive of the agency, said patients are being used as pawns in the dispute and consequently, are suffering anxiety and stress.
In a separate development, Siptu has denied reports that it made a new claim for a 35-hour working week for its non-nursing members in the health service.
Nurses stepped up their industrial action yesterday by announcing work stoppages in 12 sites around the country over two days.
The acute hospitals to be affected by the one-hour stoppages on Tuesday will be Sligo General Hospital, Louth County Hospital and Bantry General Hospital. And mental health services will be affected in three areas; Sligo/Leitrim, Dundalk/Louth and west Cork.
On Wednesday, stoppages will take place at St James's Hospital, Dublin, Portlaoise General Hospital and Ennis General Hospital.
Mental health services will also be affected in Laois/Offaly and Clare, as well as at St Patrick's Psychiatric Hospital in Dublin.
Members of the INO and PNA will stop work between 11am and noon. The 40,000 nurses nationwide will also continue their work-to-rule, which involves not dealing with non-essential phone calls or carrying out clerical or IT duties.
The nurses are seeking a 10.6 per cent pay rise and a 35-hour working week. At present, they work a 39-hour week.
Mr Mulligan said the nurses' action was counterproductive.
"It's harming patients, the very people nurses say they are advocates for," he said.
Procedures are being cancelled, causing anxiety and stress to patients and unnecessarily damaging the reputation of nursing in this country."
He said there would be more day-patient and outpatient services deferred in the coming week because of the escalated action.
However, Dave Hughes, INO deputy general secretary, denied that their action was causing damage to the reputation of nursing.
"The very notion is patronising," he said. "Would he say that to the consultants or to the porters or general workers?
"Nurses are entitled to speak up and take action when they need to."
He said they had gone out of their way to ensure patients were not affected by their action in spite of the HSE, who he claimed were ringing around all of the hospitals to find hard cases to present to the media.
Though not meeting to discuss the issues at the centre of the dispute, the unions and the HSE will discuss plans tomorrow to deal with the affect of the work stoppages in the coming week.
And, in response to reports that Siptu had served new claims of a 35-hour working week for non-nursing staff in the health service, the union said it had been pursuing claims to have the working hours of all its members in the health service reduced since 1980.
It had renewed the claim last August, long before the current nurses' dispute, a spokeswoman said. She said the only recent development was that the union had sought a meeting with the health service employers to discuss and progress the claim.
Meanwhile, Minister for Health Mary Harney is to address Siptu's national nursing convention in Castlebar tomorrow.
Siptu nurses took part in the benchmarking process and are not involved in the current dispute, but will benefit from any negotiated settlement.
