School principals and a teaching union have clashed over plans for industrial action in a pay dispute.
A row has broken out between the Association of Secondary Teachers of Ireland (ASTI) and the National Association for Principals and Deputy Principals (NAPD) amid claims that industrial action will hurt students.
Principals chief Kay O'Brien warned the ASTI that next week's action would split staff rooms, prompting teachers' union president Sally Maguire to hit back accusing the NAPD of backing pay cuts.
The ASTI, which represents 17,000 teachers, has planned to stop holding meetings with parents outside school hours, refused to take on additional middle-management roles without pay and asked teachers to opt out of covering for absent colleagues.
The industrial action begins on Wednesday.
Ms Maguire said principals are part of the union and would have voted against the Haddington Road agreement.
"ASTI principals and deputy principals have the same concerns as teachers in relation to the education cutbacks, the worsening of working conditions in schools, the diminishing of students' education, and the unprecedented number of new initiatives which are being introduced in schools without adequate resourcing and at a time when schools are operating with skeleton staffs," she said.
"Ninety-five per cent of principals and deputy principals are undertaking duties previously carried out by middle-management teachers as a result of the moratorium on middle-management appointments.
"While the ASTI accepts that its industrial action will involve administrative headaches for principals, deputy principals, and all teachers, this disruption will have little significance compared to the destructive impact of the education cuts on the lives of students, the working conditions of teachers and the fabric of schools."
Ms Maguire reacted to a letter from the NAPD in which president of the organisation Ms O'Brien said the industrial action would create an appalling vista for its members.
"The impact of such directives will be divisive, destructive of collegiality, and diminish the capacity of schools to meet the needs of students," she wrote.
"The uncertainty now generated by this decision casts a long shadow over the new academic year. The potential to disrupt already brittle school climates is immense."
Disruption from the ASTI action could hit two-thirds of the country's schools.
The Government has insisted that Haddington Road is not up for renegotiation and Education Minister Ruairi Quinn warned earlier in the week that some teachers risk losing their jobs over the dispute.