Members of the Teachers Union of Ireland have overwhelmingly endorsed a mandate for industrial action over pay discrimination.
They voted by a margin of 92% to 8% to endorse the mandate, up to and including strike action.
In a statement released this evening, the TUI said it is frustrated by the Government's "inaction" on the issue of pay inequality, and it is calling for "real engagement" from the Minister for Education and Skills, Joe McHugh.
The statement says the ballot is a clear indication that members are united in solidarity with new and recent entrants, and are prepared to take industrial action.
TUI President, Seamus Lahart, said progress has been made in the campaign, but members have run out of patience.
"This ballot result makes clear that TUI members, regardless of career stage, are united on this issue and are willing to take action, up to and including strike action, unless further progress is made without delay. Minister McHugh should take heed of our resolve."
Mr Lahart said politicians have spoken of their commitment to restoring the principle of equal pay, but "this has yet to be translated into practical action."
He said pay discrimination is the "single greatest cause of the crisis of recruitment and retention in schools across the country."
The statement says that the largest differences in pay between those employed before and after 1 January 2011 occur in the early years of employment, with new entrants to second level teaching earning 14% less on initial appointment, and 10% less in the first 10 years than they would have before the introduction of cutbacks.