“We know that in areas with high absence, a particular issue can be the availability of supply staff,” Education Secretary Nadhim Zahawi said in a letter to headteachers, published on Thursday.

The minister said his department would work with the education sector “to offer advice to ex-teachers who want to provide support to schools and colleges.” Saying that rehiring former teachers is “the best way to boost the temporary workforce available to the sector,” Zahawi called on headteachers to use their “own professional and personal networks to encourage others to sign up to offer temporary help.”

He added that the government is also discussing best “flexible curriculum delivery models” for those schools that are suffering “the most acute” staffing shortages.

According to the department’s statistics for England, 2.4% of teachers and school leaders and 2.1% of teaching assistants and other staff in state-funded schools were absent on December 9 due to Covid-related reasons. Both numbers are up from the previous week, with some schools forced to finish the Autumn term earlier than scheduled due to staff absence.

The increasing pressure caused by Covid infections on schools and concerns over the transmissibility of Omicron prompted the Teachers’ Union NASUWT to this week urge the government to consider “the immediate introduction” of additional measures to slow the spread of infection and to “minimize further disruption” to lessons. In an open letter, published on December 13, the union suggested canceling non-essential activities, moving to online staff and parental meetings, and mandating staff “working from home where appropriate.”