Leaked draft government guidance for schools about how they can safely bring all pupils back in September has been described as “fantasy” and “undoable” by a teaching union.

The Department for Education 16-point plan revealed today says there should be no face coverings for pupils or teachers, on Public Health England advice, because they would interfere with teaching and learning.

It also states that children should be seated facing forwards in the same direction and not at circular tables, while teachers are advised to keep 2m away from pupils, at the front of the class, and away from colleagues as much as possible, as if in a supermarket.

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But Mary Bousted, joint general secretary of the NEU teaching union, responding to the leaked material, said:  “Much of it is completely undoable in schools of our sizes and in classes of our sizes, so it looks like a plan for schools in England that don’t exist.

“The idea that teachers can stay 2m away from pupils in front of the class all the time - that is a fantasy world.

Coronavirus: School reopening plan ‘won’t work in reality’

“And there isn’t the space in many classrooms for teachers to keep 2m apart, and the idea that little children or even adolescents are not going to invade your personal space and come much closer than 2m is simply just not going to be tangible.”

Dr Bousted also said it wouldn’t be possible for pupils in some classes to be seated facing forwards. “In many classrooms, the reason why desks are in groups is to make the best use of the limited space, so this is a plan for schools that do not exist in England and for pupil-teacher ratios that are much lower than in England,” she added.

“Given the size of our schools and the number of pupils in them, this is not a plan which is going to work in reality. Our schools are too small and we’ve got too many pupils in them.”

The guidance was leaked to the Huffington Post. But Tes understands it is still in draft form and could yet be changed following consultations with teaching unions. A final version is expected to be released by the DfE on Thursday.

It also says schools should not put in any staff rotas from September or implement any physical distancing that would require extra space or make it impossible for all pupils to return full-time.

But the NEU says this could pose a risk to teachers who are more vulnerable to coronavirus.

Dr Bousted said: “If the requirement is going to be that clinically vulnerable teachers or those living with clinically vulnerable relatives are going to be in school for six-and-a-half to seven hours a day with no PPE [personal protective equipment] and with no social distancing then the government is going to have to take responsibility for the potential consequences of that.”

Geoff Barton, general secretary of the Association of School and College Leaders, said the process of returning all children to school was “going to be the art of the possible, rather than an ideal solution”.

“The government expects all pupils to be back in school or college full-time in September, and this is obviously what we all want to see,” he said. “But this has to be done in such a way that it doesn’t spark a new wave of coronavirus infections and plunge us straight back into a lockdown, and that is what the government guidance is aimed at achieving.

“We are urging the government to have a plan B in place in the event that we arrive at September and the situation with coronavirus is too precarious to allow a full reopening. Frankly, it seems to be on a knife-edge at the moment.”

A DfE spokesperson said: “Pupils have been returning to school since 1 June - we’ve already given primary schools the flexibility to invite more children back if they have the capacity, and 1.5 million children were in school at the end of last week.

“We’ve said we want to see all children back at school in September - returning to full primary and secondary class sizes in a safe way.

“We continue to engage with school leaders, teaching unions and the wider sector about our plans and will publish full details later this week.”