Over a million pupils are now off school as a result of Covid, up from 839,700 the previous week, and a record high since pupils returned to the classroom in March.

This includes 774,000 children who have been forced to self-isolate because of a case at school, representing a 32 per cent increase in the space of a week, according to the latest official data.

Figures published on Tuesday by the Department for Education (DfE) show that 14.3 per cent of all children in England were not at school last Thursday due to a Covid-related reason, up from 11.2 per cent the week before.

On June 28, The Telegraph launched a campaign calling on ministers to put children first as the country recovers from its Covid lockdowns, with action to bring an end to the disruption in schools.

The latest figures reveal that as well as the 1,050,000 children who are off school due to Covid, there are almost half as many again who are absent from school but not directly due to Covid.

Overall absence rate stands at 32.7 per cent in secondary schools

The overall absence rate in schools is currently 23.3 per cent, which rises to 32.7 per cent for secondary school pupils, according to official figures.

Of the 23.3 per cent of pupils off school, 14.3 per cent of these are off school for Covid-related reasons.

That leaves another 9 per cent – roughly 678,915 pupils – who are not in school but the reason for their absence has nothing to do with Covid. This is almost double the proportion of pupils who are usually absent from school, figures show.

Teaching unions have warned that children could be pulled out of the classroom in final week of term amid fears that the "pingdemic" could scupper family holidays.

The Association of School and College Leaders (ASCL) said there is a risk that families will withdraw their children to avoid them having to potentially self-isolate at the start of summer.

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Geoff Barton, general secretary of ASCL, said: "We are concerned about parents keeping children at home over the last days of the summer term to avoid the risk of them being asked to self-isolate and this interfering with family holidays.

"We are not casting blame on parents because we understand the importance of holidays after such a torrid year, but we would encourage attendance where children are not ill or self-isolating."

He said there are currently "very significant" levels of pupil absence which are nothing to do with Covid.

Meanwhile, James Bowen, director of policy at the National Association of Headteachers, said he has been hearing reports of parents saying they will keep their child off school this week to "avoid being asked to self-isolate during the school holidays".

There are now 47,000 children who have tested positive for the virus, up from 35,000 the week before, the DfE data shows.

Another 34,000 children are suspected of having the virus and 160,000 are self-isolating because of contacts outside the school gates.

And 35,000 are at home because their entire school has closed due to Covid, almost double what it was a week before.