The country's largest secondary teachers' union is warning of school closures as a dispute continues over the Lansdowne Road pay agreement.

ASTI advice - seen by The Irish Times - warns that teachers could lose up to €6,700 in increments, and others could face redundancy.

The union says there may be school closures at the start of the next academic year, by secondary teachers who are against the new Lansdowne Road deal.

Members voted last week to reject the agreement.