Mr Zahawi is launching a major campaign on Monday aimed at encouraging former or retired teachers to rejoin the profession as supply teachers during the spring term.

‘National mission to protect education’

“Whether you are recently retired or trained as a teacher and have moved profession, I urge you to consider whether you might be able to spare even a day a week to bolster the numbers of supply staff available throughout the country,” he said.

“Don’t let anything get in the way of coming forward to join the national mission to protect education.”

Dozens of schools around the country started to send children home early for the Christmas holidays owing to staff sickness.

School leaders and academy chain chiefs are preparing for the possibility of having to switch to online learning next term, with some pupils asked to take laptops and textbooks home before Christmas just in case.

Those eligible to apply as supply teachers can expect to receive targeted communications encouraging them to participate.

The Government is also working with the teacher training programme provider Teach First, which offers university graduates a fast track into the teaching profession.

After completing the two years of teaching at a school in a deprived area, participants in the scheme often go on to work in a range of private sector roles such as accountancy, banking or consultancy.

Russell Hobby, chief executive of Teach First, said: “Given the challenges that schools now face, we want to see what more can be done to help – including how we, and those of our alumni who have trained as teachers but currently work outside the profession, may be able to support schools to remain open safely in the new year.”