Education secretary Gavin Williamson has accused the NEU teaching union of being “content to put pupil progress on hold” after its call for schools to close again.

Mote than 150,000 NEU members have signed a petition since the weekend calling for schools to close, as before, to all but vulnerable children and those of key workers - with union joint general secretary Kevin Courtney describing schools as “an engine for virus transmission” and highlighting a fiftyfold increase in infections in secondary schools since September.

However, the education secretary claimed today that the union’s position was “isolated”, and said he was particularly concerned about disadvantaged pupils missing out if schools closed.

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Writing in The Telegraph today, Mr Williamson said: “Every day they spend out of school is another that risks allowing a gap between them and the rest of their class to widen.

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“This is why I strongly disagree with the leadership of the National Education Union, who appear content to put the progress of those pupils in particular on hold, by calling for us to close schools.

“When the risks are being managed, when the benefits of being in school are so clear, this seems to be an isolated position that doesn’t put the best interests of pupils first.”

But Mr Courtney today hit back, saying the NEU proposals were “nothing to do with putting progress on hold”.

“They are everything to do with breaking the chains of virus transmission in schools and the best ways of getting to more continuity of education in this crisis,” he said.

“There are far more children being sent home in disadvantaged areas of the country where the Covid rate is higher, so we’re not taking any lessons from Gavin Williamson about looking after disadvantaged kids.”

Yesterday the NEU accused Mr Williamson of being deluded and detached from reality for claiming “there is really nothing we wouldn’t do” to support pupils’ education during the coronavirus pandemic.

Research by Tes over the summer found that a third of teachers believed the gap between disadvantaged pupils and their peers had widened to “a gulf” under the pandemic.

However, recent research shows that it does not appear to have increased as a result of exams being cancelled.

Mr Williamson also said today that universities are piloting rapid Covid testing for schools in which results could be available within the hour.