The president of the ASTI has hinted that a short-term deal could be reached to stop further closures of secondary schools.
Ed Byrne was speaking as around 500 schools were shut on the first of seven days of strike action, over pay inequality.
An indefinite strike could begin on Monday week as ASTI members refuse to continue unpaid supervision and substitution duty.
Ed Byrne says the union will continue campaigning for payments - but does not want schools to shut as a result:
The Education Minister, Richard Bruton, says he's disappointed at today's strike action, which has seen around 250,000 off school.
The teachers are protesting at pay inequality in the sector - but Bruton says the teachers themselves are causing inequality by not doing the same work as their colleagues.
Our political correspondent Gavan Reilly filed this report for Today FM's National Lunchtime News:
