The offer from the employers had said that schools needed "a prolonged period of stability free from industrial action and the threat of industrial action."
It also asked teachers to accept that "industrial action should only be taken as a last resort in any dispute".
The offer also said that teachers should "commit to a period free from industrial action in the context of the agreed future pay negotiation timeframes and implementation of the agreed work programme".
Union leaders subsequently said that did not mean that teachers had to waive their right to strike.
The pay offer also specified how many days and hours teachers should work.
Unions had carried out a short consultation with teachers on the offer, but that did not provide the necessary backing for the deal.