Teachers are “disturbed” by “unhelpful” speculation that schools and colleges will reopen soon amid the Covid-19 pandemic, according to the largest education union in Europe.

The National Education Union (NEU) has written to the Prime Minister asking for the Government to urgently share its modelling, evidence and plans for reopening schools.

An early return to school will result in an “increased risk” to school staff and children and it could “undermine people’s resolve to stick to social isolation”, the NEU warns.

It comes after headteachers have suggested that schools should reopen for a period before the summer holidays, rather than September, if scientific evidence says it is safe to do so.

Schools in England closed more than three weeks ago to the majority of pupils, apart from the children of key workers and vulnerable pupils, due to the coronavirus outbreak.

Members are disturbed by increasing media speculation that schools will soon be reopened

There is no indication yet as to when they may be able to reopen but the NEU is concerned that speculation about schools reopening soon is allegedly being “stimulated by unnamed Government ministers”.

The union is calling on Boris Johnson to consider the increased number of cases and mortalities among children, parents and teachers if schools were to be reopened.

The letter, from the union’s joint general secretaries Mary Bousted and Kevin Courtney, says: “Our members are disturbed, however, by increasing media speculation that schools will soon be reopened.

“We consider this speculation to be most unhelpful: it may undermine people’s resolve to stick to social isolation.”

The Government should clarify whether any plans are based on the notion that social distancing can be implemented in schools as this would be a “foolhardy assumption”, the NEU has warned.

The letter also calls on Mr Johnson to clarify whether there are any plans to establish regular testing of children and staff, increase access to personal protective equipment (PPE) and enhance cleaning as these areas are all “experiencing severe difficulties”.

It adds: “Given that an early return to full school populations will mean an increased risk to our members and the children in their care, we are writing to ask you to share your modelling, evidence and plans.”

It comes after Professor Paul Cosford, emeritus medical director for Public Health England (PHE), suggested that one of the first lockdown measures to be lifted could be school closures.

Speaking to the BBC Radio 4 Today programme on Friday, he said: “We do know that children are at very low risk of getting complications from this disease.

“The importance of children’s education, children being in school, is paramount.

“I could conceive of circumstances in which some of the restrictions are lifted sooner and some are lifted later.”

Last week, a study led by researchers at University College London indicated that school closures do not appear to have a significant effect on the spread of infections during outbreaks such as Covid-19.

Researchers found that school closures alone were predicted to reduce deaths by around 2% to 4% amid the Covid-19 outbreak in the UK, which is less than other social distancing measures.