Strikes by nurses and midwives look inevitable as Finance Minister Paschal Donohoe poured cold water on their pay demands.
Mr Donohoe took a hardline with the nursing unions as he insisted the Government will stand by the terms of the current public service wage agreement, which already commits to wage hikes.
Nurses have voted overwhelmingly for strike action to get extra pay rises.
Strike action poses the risk of having their pay rises delayed, a freeze on increments and withdrawal of a deal for recent recruits worth over €3,000 each.
Speaking on RTÉ's 'Today with Miriam' on Radio One, Mr Donohoe said: "We have a collective agreement now with all of our unions in relation to around €18bn of taxpayers' money every year. What I cannot let happen is I cannot let that agreement unravel... this is an agreement that we have to maintain and we will."
The minister pledged that the Government will continue to engage with nursing unions, but underlined that his message on preventing the current deal from unravelling was "really clear".
The Government has offered nurses a €20m pay package - but these increases would only apply to specialised grades.
The nurses want equal pay with professional grades, including radiographers and physiotherapists, and claim there is a recruitment crisis due to low wages.
Reacting to Mr Donohoe's comments, general secretary of the INMO Phil Ní Sheaghdha said it was important that the Government works to avert a strike "by engaging directly with nurses and midwives to sort this out".
She added: "The INMO has already stated that this can be dealt with within the Public Service Stability Agreement."
The executive councils of the Irish Nurses and Midwives Organisation and Psychiatric Nurses Association will decide next steps in the coming week.