Primary schools will struggle to operate smaller class sizes and encourage young children to take part in social distancing if they reopen next month, the leader of the headteachers’ union has warned.

Paul Whiteman, general secretary of the National Association of Head Teachers (NAHT), said there are a number of “difficulties” with the Government’s guidance on safely reopening schools by June 1.

He told MPs that the school leaders’ union was not consulted on specific plans, announced in recent days, to admit pupils in Reception, Year 1 and Year 6 from June 1.

Addressing a virtual Education Select Committee, Mr Whiteman said: “If social distancing is as we understand it now – the two metre rule to be applied in schools – there are very many schools that are saying it is simply impossible to achieve.”

Mr Whiteman added that it is hardest to maintain social distancing, as well as good hygiene levels, with the younger year groups.

Social distancing is going to be a massive problem

“Social distancing is going to be a massive problem,” he said.

It comes after the Department for Education (DfE) issued guidelines on Monday which said primary school class sizes should be limited to 15 pupils and outdoor space should be utilised.

The advice calls for schools to stagger lunch and break times, as well as drop-off and pick-up times, to reduce the number of pupils moving around.

It adds that schools should also consider introducing one-way circulation, or placing a divider down the middle of the corridor.

But Mr Whiteman said schools would struggle to accommodate the advised 15 pupils in their classrooms.

He said: “Our members are telling us that their building sizes on average would only accommodate classes of 10 to 12, rather than 15.

“So straight away we’re getting into some real practical difficulties about whether the Government’s ambition can be practically accommodated.

“Let alone all the fears that parents have about bringing their children back into school, and the fears of the workforce too.”

He told MPs that there “isn’t enough understanding of the scientific basis” for the return to schools next month for confidence to exist among parents.

His comments came after the Government announced its ambition for all primary school pupils in England to go back to school for a month before the summer.

The Government expects children to be able to return to nurseries and childcare settings, and for Reception, Year 1 and Year 6 pupils to be back in school, from June 1 at the earliest.

Jenny Coles, president of the Association of Directors of Children’s Services (ADCS), also expressed concerns about the June 1 date during the committee hearing, adding that a five or six-week lead in time was needed to prepare for a return to school.

She told MPs: “Getting that parental confidence, in terms of a phased return to school, will need a lot of work by central Government, local communities and local government.

“This is not going to be something that’s going to be fixed by June 1. It’s going to take a lot of weeks and a lot of work to do that.”

Kevin Courtney, joint general secretary of the National Education Union (NEU), urged members on Tuesday not to engage with planning for a June 1 return until further advice had been issued.

Jon Richards, head of education at Unison, which represents school support staff, also advised members against making plans until a joint position was agreed with the education unions.

If schools are unable to open safely before September, because they cannot make arrangements to safeguard staff and pupils, then this position should be accepted, the NASUWT teaching union has said.

Patrick Roach, general secretary of the NASUWT, said on Tuesday: “The June 1 2020 is the date from when schools may be able to extend their opening arrangements.

“It is neither a fixed nor hard and fast date by which all schools must open and there is no requirement or obligation currently on any school to reopen to more pupils from that date.”

He added that nothing that has been said by the Government which has changed the union’s position that no teacher should be expected to go into a school until it can be shown that it is safe to do so.

It came as a poll from the NEU suggests that a third of parents do not immediately plan to send their children back to school once lockdown measures are relaxed.

The survey of 1,000 parents found that nearly half (49%) said they would send their children back to school as soon as it reopens, but 33% said they plan to delay the return.

Rebecca Long-Bailey, Labour’s shadow education secretary, said: “There is still no realistic guidance for how social distancing will be kept in place with the age groups that will return first, how staff and families of children will be protected, or how class sizes of 15 will be achieved with the resources schools have.

“The Government must urgently convene education unions and the profession to create a workable plan for the reopening of schools when the science indicates it is safe to do so and which has the confidence of all those affected.”

A DfE spokesperson said: “We want children back in schools as soon as it is safe to do so because it is the best place for them to learn and benefit from important social interactions.

“Plans for a phased return of some year groups from June 1, at the earliest, have been drawn up in close consultation with the sector and are based on the best scientific and medical advice.

“The welfare of children and staff has been at the heart of all decision making.

“We have engaged with the unions throughout the past seven weeks and will continue to do so, including to develop further guidance for the sector.”