A group of 22 academy chains has warned that the impact of lost learning during the coronavirus crisis could be “irreparable” if schools do not open to more pupils soon.

Multi-academy trust leaders from across the country have called for “improved dialogue” on the subject of returning to school from 1 June, arguing that “some of the debate over reopening has been unhelpful and doesn’t reflect our sector”.

In a letter to The Times, the leaders warn that prolonged absence from school is “concerning” for any child, and “calamitous” for disadvantaged pupils.

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“We need to abide by scientific advice, collaborate and welcome children back to school,” the letter says.

It is signed by the leaders of Reach South Academy Trust, Diocese of Ely Multi-Academy Trust, Leigh Academies Trust, Active Learning Trust, The Beckmead Trust, NET Academies Trust, Unity Schools Partnership, Inspiration Trust, Academies Enterprise Trust; Wave Trust, The Elliot Foundation Academies Trust, David Ross Education Trust, Ormiston Academies Trust, East Midlands Education Trust, E-ACT, Harris Federation, Outwood Grange Academies Trust, Star Academies, Future Academies, Delta Academies Trust, Cabot Learning Federation and Dixons Academies Trust.

The evidence surrounding the safety implications of reopening schools has been the subject of fierce debate in the sector.

Coronavirus: Safety fears about reopening schools

It was reported today that a study being considered by the government suggests that children are “not the primary drivers of Covid-19 spread” in schools.

A senior member of the Scientific Advisory Group for Emergencies (Sage) subcommittee on schools reportedly told The Daily Telegraph that the government has examined the Australian study as it considers a phased reopening of primary schools from 1 June.

However, the British Medical Association said last week that the available evidence on reopening schools is “thus far conflicting”.

It added that a recent study from Berlin had shown that children were just as likely to be infected as adults and may be just as infectious.

“In light of these studies...the view of the members of the PHMC [Public Health Medicine Committee] is completely aligned with the NEU [teaching union] that, until we have got case numbers much lower, we should not consider reopening schools,” the BMA said.

The news comes as a growing number of local authorities continue to defy the government over its 1 June reopening target.

Both Liverpool City Council and Hartlepool Borough Council have said schools will only be open to vulnerable pupils and the children of key workers on 1 June.

And Andy Burnham, mayor of Greater Manchester, has reportedly said schools should only reopen when it is safe for both teachers and pupils.

Individual headteachers have also stated their intention to go against the government’s plan.