Laura Doel, director of NAHT Cymru, said: “We hope that when the Minister says in his statement that the Welsh Government will work with education stakeholders to collect intelligence on the emerging situation, this will include a discussion about the mitigation measures currently in place.

“NAHT Cymru has made its position clear, the existing measures do not go far enough to support schools. High levels of staff absence cripple schools' ability to stay open, let alone begin to tackle the challenges of curriculum reform and new ALN legislation.

“Just today, Qualifications Wales published a report 'Qualified for the Future', looking at new qualification arrangements as part of curriculum reform, and called upon practitioners to join in that development process. When schools can barely stay open on existing staffing levels, there is no way they can be released from the classroom to work on such reforms. That puts curriculum development in jeopardy when we need the profession to be front and centre of such ambitious reforms.

“We urge the Welsh Government to commit to reviewing the measures and reintroduce mitigations that had little or no impact on the delivery of education, like staggered session times, to help keep staff and pupils in school.”

In response to the additional funding to help with ventilation problems, Ms Doel added: “We are pleased that additional funding will be made available to schools and we will continue to work with the Welsh Government on the issue of ventilation to ensure that schools have what they need to tackle the problem. It is crucial that schools do not end up having to foot the bill to fix ventilation problems.

“NAHT Cymru was deeply concerned from the outset that the Welsh Government had earmarked such a significant amount of money on an untested and yet-to-be trialled proposal. Reallocating those resources to addressing ventilation will be much more beneficial to schools. Now that ozone machine plans have been ditched, we do also need support for schools for cleaning, as well as ventilation.

“Schools have been thrown a lifeline by the extension of hardship funding to cover covid-related staff absence and we are grateful that our members' views have been listened to.”