The Irish Nurses and Midwives Organisation has described as "greedy and opportunistic" the decision to pay newly recruited nurses 20% less than the going rate.
It follows an announcement by the HSE that its to take on 1,000 new nurses and midwives in the new year, as the government lifts the ban on recruitment in the health service.
The graduate nurses will be deployed across areas that currently rely on agency staff.
The Irish Nurses and Midwives Organisation has welcomed the announcement that new contracts are being filled.
But General Secretary of the INMO Liam Doran has said that graduate nurses must be paid properly: