The executive committee of the Teachers' Union of Ireland (TUI) has unanimously decided to recommend rejection of the new public service agreement because of what the union calls its "failure" to end pay discrimination.
In a statement, the TUI said it welcomed the fact that the deal - "Building Momentum - A New Public Service Agreement 2021-2022" - provided for general pay increases, the first for public servants in over ten years.
It said it also recognised the severe financial difficulties caused by the coronavirus pandemic to so many working people.
However, the union said that ten years on from the imposition of cuts to new entrant pay, it could not recommend acceptance of proposals that would continue to result in colleagues being paid lesser rates of pay for carrying out identical work.
Over 19,000 TUI members are to balloted on the agreement in the new year.
President Martin Marjoram said: "We are just weeks away from the tenth anniversary of the unilateral imposition of cuts to new entrant pay, but despite progress, its corrosive effects continue to damage the education system.
"Regrettably, the limited measures contained in this proposed agreement will not end the ongoing scandal of pay discrimination for second level teachers employed on or after 1st January 2011 and the proposed agreement does not address it at all for the other recruitment grades in which TUI represents members."
Mr Marjoram said there had been "a teacher recruitment and retention crisis at second level for many years" as a result of pay discrimination.
He pointed to a survey carried out in over 130 second level schools earlier this year which showed that over the previous 12 months, 97% of schools had experienced teacher recruitment difficulties, while 77% had advertised positions for which nobody applied.
TUI members took strike action earlier this year over the issue.
Mr Marjoram said: "Even with this proposed agreement, the largest pay discrimination would still occur in the early years of employment.
"New entrants to second level teaching would still earn €6,500 or 15% less upon appointment than someone who entered the profession prior to 2011. The loss in career earnings would still be over €80,000."
He said the agreement does "nothing to redress the ongoing pay discrimination" in new entrant grades including assistant lecturer, Youthreach resource person, BTEI adult educator, adult guidance counsellor/coordinator, adult literacy organiser and community education facilitator.
Mr Marjoram said many new entrants "are voting with their feet and leaving the profession".
Earlier, the central executive committee of the Irish National Teachers' Organisation decided to recommend that its 42,000 members accept the proposals in the agreement.
They are also set to vote on the deal in the new year.