Up to 45,000 third-level students are likely to be affected by industrial action planned by the union representing lecturing staff at the State's 14 Institutes of Technology.
The 2,700 members of the Teachers' Union of Ireland (TUI) at the colleges will ballot from today on strike action in a dispute over the position of part-time lecturers.
The TUI is seeking approval for a one-day stoppage because it said the Department of Education had failed to improve the position of part-time lecturers despite protracted negotiations.
While the initial ballot is for a one-day stoppage, union sources said that if the situation was not dealt with, the action would be stepped up.
Among those affected will be the 22,000 students at the largest third-level institution in the Republic - the Dublin Institute of Technology.
If members vote in favour, the one-day stoppage is likely to take place early in the next academic term, union sources said, and it will involve the complete withdrawal of teaching. At this stage it has not been decided if the stoppage will take place simultaneously at all the colleges.
Permanent lecturers are being asked to vote in support of their part-time colleagues, in a letter circulated to members by the TUI yesterday. The action is unlikely to lead to the closure of the colleges, as the dispute does not involve staff from other unions.
A draft agreement with the Department of Education was recently finalised, in which the Department conceded that certain part-time lecturers would be given equivalent part-time teacher (EPT) posts - which entitles them to sick leave, maternity leave and pension rights.
However, the Department has since stated that agreement on the EPT posts can be reached only after there is also agreement on two other types of contracts - fixed purpose and hourly paid contracts.
The TUI has pointed out that it has no difficulty agreeing on these contracts, but the union does not want these agreements tied to the EPT issue, which has long been a source of tension in the colleges.
Fixed purpose contracts refer to posts required only for a short period to deal with a specific academic requirement. Hourly paid contracts involve contracts for staff who are paid on an hourly basis and who do not qualify for EPT status.
To link all the contracts together will slow the whole process of negotiations down, union sources said yesterday.
In its letter to members the TUI said it "insists that this agreement be implemented now for the existing part-time lecturers in the current year".
Pay is decided in the Institute of Technology (IT) sector on a collective basis - with the council of directors representing the views of the 14 institutes in conjunction with the Department of Education.