The ASTI is due to meet with officials from the Department of Education today, ahead of an escalation of industrial action on Monday.
17,000 secondary teachers are due to withdraw from all supervision and substitution duties after the mid-term – which could see the indefinite closure of hundreds of schools.
Last week, the union staged an official strike over pay levels for new entrants to the profession. Six more days of strike action are scheduled to take place.
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