Just one in five councils are advising schools to reopen on 1 June, new research suggests.

And two-thirds of authorities cannot guarantee that schools will reopen to more children in Reception, Year 1 and Year 6 in line with the government’s plan, according to a snapshot survey.

Over the course of 48 hours, BBC Breakfast carried out a survey of the 150 local authorities that have responsibility for primary schools.

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Of the 99 councils that responded, just 20 (one in five) said they were advising schools to reopen to more pupils on 1 June.

And 68 (two in three) said they could not guarantee schools would reopen more widely on that date.

The news comes on the day that the scientific evidence underpinning the government’s decision to reopen schools to more pupils from 1 June will be made public.

A spokesperson for No 10 told Tes that the evidence from the Scientific Advisory Group for Emergencies (Sage) will be published today (Friday).

Meanwhile, a group of leading scientists known as the “Independent Sage” committee has warned that a 1 June reopening of schools would be too early for pupils to return to classrooms safely.

The BBC survey also found that 15 local authorities, mainly in the North West of England, said they were not advising schools to open more widely.

Meanwhile, 11 councils said they were still considering the issue, and 53 reported that they were leaving the decision up to individual schools.

A spokesperson for the Department for Education told the BBC: “We want children back in schools as soon as possible because being with their teachers and friends is so important for their education and their wellbeing.”