The ASTI pesident has said the most disappointing aspect of the proposals for reform in the public sector is that they show "a total lack of respect and trust in teachers".
The Association of Secondary Teachers in Ireland will tomorrow debate a motion recommending rejection of the deal on pay and public sector reform at its annual conference in Galway.
Earlier today delegates of the Teachers Union of Ireland rejected the agreement while members of the Irish National Teachers Organisation narrowly supported it.
ASTI President Joe Moran told his delegates they had to seriously consider what way they were going to vote.
"Whatever we decide this week, it is essential that the full strategic and contextual considerations of both acceptance and rejection are fully comprehended by every ASTI member," he said.
"Above all we must remain resolute, confident and united at this crucial juncture."