One of the country's largest public sector unions is backing the Lansdowne Road 2 pay deal.
Some 77% of IMPACT members have voted in favour of the agreement, which is set to follow Lansdowne Road.
The union said however that rapid action on pay iniquities is needed in order for them to fully commit to the deal.
The announcement comes just days after the INTO said it would reject the deal over pay equality for new teachers.