Thousands of school support staff are to be balloted for industrial action as the Government announced plans to hire almost 1,000 more special needs assistants later this year.
Education Minister Richard Bruton said the 975 new jobs will be available from September with schools being notified of their allocations to ensure pupils can enrol for the new term.
But the Impact trade union accused the Government of leaving staff with no guarantee of a job before schools break for the summer for the fourth year in a row.
Deputy general secretary Kevin Callinan said there is no practical reason why schools cannot get the allocations in April or May to plan for the new term and allow for the redeployment of SNAs in a "dignified, effective and timely way".
"If it happened one time, it would be unacceptable. But it happens every year - and that shows contempt for SNAs, and for the children, parents and schools they serve," he said.
Mr Callinan said the issue over allocations and longer term contracts is to give SNAs the same job security as the teachers they work side-by-side with in the classroom.
The Department of Education said the number of SNAs has increased from 10,575 in 2011 to 13,990.
There are 700 more children with special needs entering third level now than two years ago, an increase of 31%, it said.
Mr Bruton said: "Special needs assistants have continued to play a key role in helping children to participate and progress. The extra posts I am announcing today will ensure that every child that needs access to SNA support can receive this support.
"That is my priority."
The Impact ballot on industrial action will take place at the start of the next school term.
- Press Association