Education Minister Ruairi Quinn has come under fire from teachers after warning that small schools could fall victim to further cuts.
Two of the country's main teachers' unions have warned that Government cuts to the public sector would breach the Croke Park Agreement, which could lead to industrial action.
Irish National Teachers' Organisation general secretary Sheila Nunan hit back at Mr Quinn, who said the education sector does not understand the seriousness of the financial crisis.
"We get it. There is no lack of comprehension in this room or in the schools represented about the economy," said Ms Nunan in an address at the annual INTO congress in Co Kerry.
"We absolutely get it, Minister. We do not need to be reminded of the economic woes of the country or the incompetence of the previous government."
Ms Nunan said the Croke Park Agreement had helped establish peace between the Government and the public sector, which would be lost if the pact were broken.
Echoing Ms Nunan, Teachers' Union of Ireland general secretary John MacGabhan said all bets would be off if the Government breaches the Croke Park Agreement. He also argued that cuts in education are continuing to affect the most vulnerable and schools that are already disadvantaged.
The deal was made in 2010 promising no further reductions in workers' pay rates from 2010 to 2014 and no compulsory redundancies. In exchange, public servants agreed to be flexible in their work to change the way the sector runs, to help improve how it works while reducing costs.
Mr Quinn was heckled by placard-waving protesters at a conference when he announced there are limits on the number of teaching posts the Government can afford to fund. He also pointed out that 80% of the current education budget is allocated to pay and pensions.
He said: "This Government has protected education as much as it can. Far greater reductions in the number of public servants are being made in other sectors relative to those in schools. But there are limits on the number of teaching posts we can afford."