The ASTI has warned they will be forced to take no other option other than undertake industrial action if teaching staff are made redundant.
The news comes in the wake of a recent pay dispute with the Department of Education. It is understood that the union are angry with the department after it recently announced plans to make teachers surplus to requirements redundant.
However The Association of Secondary Teachers, Ireland (ASTI) say they will fight such an action balloting its members on industrial action.
The prospect of strike could be mean tens of thousands of students preparing for their State exams in June would be unfairly disrupted in the process.