Headteachers have today warned that government plans for all primary school children to return to school before the summer for a month are “wildly optimistic, to the point of being irresponsible”.

In a document published today, the government also reiterated plans announced by the prime minister yesterday that Reception classes and pupils in Years 1 and 6 could return to school from 1 June.

But the NAHT school leaders’ union said the plans gave “false hope” to families.

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General secretary Paul Whiteman said “The government’s determination is for all primary school children to return to school before the summer for a month. This is not currently a feasible scenario. The availability of school staff, the sheer number of pupils, and the sizes of school classrooms and corridors, combined with the need for social distancing measures, mean that the government’s calculations simply don’t add up.

“Based on the current trajectory, it seems wildly optimistic - to the point of being irresponsible - to suggest that we will be in a position to return all primary children to school within the next seven weeks. This will give false hope to families and parents that we are further along the road to recovery than we actually are.

“School leaders do not want to see classrooms empty for a day longer than they need to be. But there is not a school leader in the land who wants to risk admitting more pupils unless it is safe to do so.”

The Department for Education has been contacted for comment.