The ASTI has confirmed it will withdraw from substitution and supervision duties in secondary schools from Monday.

It means 400 schools are now unlikely to open after the midterm break.

It follows negotiations between the Department of Education and the teaching union at the Labour Court in long standing row over pay and conditions.

The ASTI says its members will turn up for teaching duties on Monday - however boards of management had previously warned they couldn't open if all duties are not covered due to health and safety concerns.