Schools will be forced to close during strike action by thousands of classroom assistants next Wednesday, a union warned today.
NIPSA claimed new workers would lose around £2,000 sterling a year under changes to how pay is calculated.
Assistant secretary Alison Millar said members had been driven to take the step after negotiations failed to break the deadlock. "People don't take action of this magnitude lightly. Enough is enough, we are at the end of our tether," she said.
"We have been promised a resolution would be found, we have been involved in weekly negotiations, but have seen no movement from employers.
"We have a number of principals already who have said that schools will close for health and safety reasons."
NIPSA is calling on all 2,500 members to walk out. Just over 1,000 have voted in favour of striking but the union believes many more will take part.
Managers want to calculate the pro-rata hourly rate on a full-time 36-hour week when it has traditionally been 32.5. There have been compensatory increases to the amounts staff can earn within their pay band.
Salaries of existing workers will stay the same, but the change will affect new recruits.