The Education Minister says he hopes to have cooperation from the Association of Secondary Teachers of Ireland (ASTI) in the event of a strike so that schools can stay open.

Hundreds of schools could face closure if members of the ASTI vote for industrial action over pay.

18,000 teachers who are members of the union are being balloted, with the union recommending a vote in favour of industrial action.

In the event of a strike, the Department of Education would have to hire in temporary staff to keep around 400 schools open, and it hopes the union can give them enough notice to vet the temps.

Minster Richard Bruton says he has written to the ASTI.

"Obviously we would need cooperation of the principals," he explained. "We also need to put in place systems for recruiting and vetting those who would do the supervision work, so we don't interfere with children's education in the course of this dispute.

"Obviously we depend on cooperation from the ASTI, and we have sought that," he added.

General Secretary of the ASTI is Kieran Christie stressed: "We wouldn't like to preempt the outcome of those ballots, and we've made no decisions in relation to the actions that may be taking place until every last vote has been counted."

In addition, some Junior Cert students risk losing 10% of their marks because their teachers are not cooperating with the revamped exam.

The union says Minister Bruton could avoid this situation – but he says it is up to the union.

"We cannot be changing the curriculum and the assessment method because some people object to it," he argued.

"I continue to ask the ASTI to allow that test be completed within ASTI schools, so young people doing the Junior Certificate can fulfill that piece of the assessment."