The Teachers' Union of Ireland is to ballot members for industrial action up to and including strike action if the Government decides to impose the Croke Park II proposals.
The union's delegate conference in Galway unanimously passed an emergency motion.
It would see members withdraw from cooperation already conceded under the first Croke Park agreement with immediate effect if the latest proposals are imposed.
It would also direct all members to refuse to engage in any measures in Croke Park II.
It instructs the executive committee to conduct a ballot for industrial action "up to and including strike action" in the event that the Government or ICTU decide to impose the proposals.
That motion passed by the conference also states that in light of the TUI's rejection of Croke Park II by a margin of 86%, the executive committee should call a rally of all public sector workers to consolidate a movement against the new public service agreement.
The conference passed a second emergency motion calling for cooperation with other unions in opposing the proposed deal.
That motion also demands that the Government target a combination of additional income tax on the earnings of the top 5% of "income units" in Ireland, along with the introduction of a progressive wealth tax instead of cuts in the public sector.
Quinn warning over frontline services
Minister for Education Ruairi Quinn has warned teachers that the Government will have no alternative but to hit frontline services if the Croke Park II proposals are rejected.
After addressing the conference, Mr Quinn said that the gap in budgetary figures faced by Minister for Public Expenditure and Reform Brendan Howlin would not disappear because of a vote rejecting the Croke Park II proposals.
He said the Government would have to deal with that.
Asked whether he was prepared to walk through the lobby and legislate to implement Croke Park II if it is rejected by unions, Mr Quinn said they would have to wait and see the overall vote of public service unions on 17 April.
He said they would then get advice from those who had led the negotiations.
Mr Quinn said that until he got advice from his colleagues in Cabinet, he was not going to engage in any speculation in public.
Asked about the threat of industrial action including strikes, he said there were many steps to go before that would arise.
INTO debates Croke Park II motion
INTO members have debated a motion related to Croke Park II in closed session.
The motion noted the Government had signalled its intent to legislate for pay cuts in the event of the LRC proposals being rejected.
It called on the union's executive put in place a strategy to defend members in all eventualities.
The INTO confirmed that out of 22 members who spoke on the motion most indicated that they intended to vote No to the Croke Park proposals.
The motion secured almost unanimous approval from the 800 delegates present.
ASTI - no threat to State exams
Separately, the President of the Association of Secondary School Teachers of Ireland, Gerry Breslin, has said that his union is not considering taking any action that would impact on State exams.
The union is balloting its members on Croke Park II and has called for the Labour Relations Commission's proposals to be rejected.
Speaking on RTÉ's Morning Ireland, Mr Breslin said that should the proposals be rejected, the union executive will then meet to discuss its strategy.
However, he said that as far as he was concerned there was no threat to State exams, and described such a suggestion as "scaremongering".
It emerged yesterday that the Teachers' Union of Ireland has threatened to withdraw from setting and marking exams at Institutes of Technology.
The move is in opposition to the Croke Park proposals, which involve the elimination of additional payments for setting and correcting exam scripts.
ASTI members heckled and showed red cards to Minister Quinn at its conference yesterday.
Mr Breslin said that while the actions of some members were "not polite", teachers were angry at the proposals and the department's failure to consult with them on changes to the Junior Certificate cycle.
Meanwhile, the General Secretary of the ASTI Pat King said that the way in which some members treated the minister at the union's conference yesterday was inappropriate.
Speaking on RTÉ's Today with Pat Kenny, he said that only ten teachers had walked out and between 15 and 20 had interrupted the minister during his conference address.
Mr King said that the vast majority of the 500 teachers attending the conference had listened to the minister.