The INTO has disputed claims by the Minister for Education and Science, Ms Hanafin, that it may not be possible to meet Government targets on class size.
The Government had promised in its Programme for Government to cut average class sizes for children under nine years old to 20 children for each teacher by 2007. But the Minister has hinted that the timeframe may have to be shifted because of the shortage of teachers and the new priority given to special needs education.
Department of Education sources said: "This is a commitment and we are not backing away from it. We just want people to be a bit more realistic about the timetable given the number of available teachers and the stress on special needs."
The Department says it would take at least 2,000 extra teachers to meet the target and that it is not feasible to recruit this number in the time set out in the Programme for Government.
Last night, the INTO claimed the target was "do-able" and it produced figures to back up its claim, based on future trends in teacher recruitment and retirement.
It claims some 1,800 new teachers will be trained next year. This includes 1,000 graduates from St Patrick's College, Drumcondra, Dublin, and Mary Immaculate College in Limerick, and 300 more from the smaller colleges.
In addition, there will 400 graduates from Hibernia College, which provides an on-line training programme for graduates. This will be augmented by graduates trained in Britain who will enter the job market here. The INTO says there will be a good surplus of teachers available next year - even allowing for retirement trends.
"The key question for the Government to answer is this - is it prepared to put trained teachers in the dole queue rather than employ them to bring down class sizes?" the INTO states.
Discussions between the Minister and the INTO to agree a framework within which class size can be reduced over the coming years appears likely in the coming week. But the controversy has unleashed strong reaction from the Opposition.
Fine Gael accused the Minister of "backtracking" on its commitments. Its education spokeswoman, Ms Olwyn Enright, said the Government was doing this because it will not fund the recruitment of new teachers. "It is disingenuous of the Minister for Education, Mary Hanafin, to use the supply of teachers as the reason behind Government backtracking on a commitment to reduce average class sizes.
"The Department of Education directly funds teacher-training colleges, and effectively manages the number of teachers graduating each year from the traditional teacher-training colleges."
Labour's Ms Jan O'Sullivan said the "reprehensible" decision proved that the Government has no shame in breaking its promises.
"The Government made a very specific commitment in 2002 that the average size of classes for children under nine would be brought below the international best-practice guideline of 20:1. This was not just a pre-election promise from Fianna Fáil - it was a commitment of both Government parties."
