In a statement issued this morning, the union said failure to resolve pay discrimination has made the teaching profession much less attractive.
Due to cost-cutting during the financial crisis ten years ago, teachers hired after 2012 still earn less than their counterparts hired before that year.
Liz Farrell TUI President said it is causing major issues for schools, according to a recent survey they conducted.
Ms Farrell said: “Ninety-nine per cent of schools experience recruitment difficulties, 66 [per cent] experience teacher retention difficulties, 75 per cent of schools advertised positions for which no teacher applied, and 70 per cent unfilled vacancies.”
She added: “The cost-of-living crisis, particularly in relation to accommodation and transport, is worsening what was already a dire situation, particularly in larger urban areas.”