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Boris Johnson has ditched his plan for all English primary pupils to go back to school before the summer, the government has confirmed.

The prime minister announced last month his “ambition” for every year group to return for at least four weeks of classroom teaching by June 21.

But education secretary Gavin Williamson told MPs on Tuesday that school sizes had posed practical difficulties in meeting the requirements to restrict classes to bubbles of around 15 pupils.

And he also refused to promise that all secondary and primary pupils would return by September.

Primary headteachers will instead be given “flexibility” to bring “the maximum amount of pupils” back to school and to decide for themselves how quickly to admit more year groups in coming weeks.

“I know that schools need time to put in place the strict protective measures we have asked,” Williamson said.

“This cautious, phased return is the most sensible course of action to take. While we are not able to welcome all primary children back for a full month before the summer, we continue to working with the sector on the next steps.

“We would like to see schools who have the capacity to bring back more children in those smaller class sizes to do so, if they are able to before the summer holidays.”

Challenged on the problems many working parents will have with childcare, he floated the idea of a “priority list” of pupils who could be admitted by schools.

“We are working to devise a priority list so that schools are able to, where they do have extra capacity, to be able to welcome more children back into those schools so that they are able to support their learning, but also their communities and including their parents who of course do need to be going out to work as well.”

Williamson confirmed the target had been dumped as the Department for Education (DfE) revealed that as of last week just a quarter of pupils eligible to return had done so.

Some 11% of pupils attended school, around one in four of the 42% who make up reception, Year 1 and 6.

In some cases, as with schools in the north west, some head teachers didn’t expand opening, but in other cases it appears parents kept their children home.

Williamson did say that numbers had improved since last week, with 70% of primary schools who responded to DfE saying they had opened their doors to more children, up from 52% last Thursday.

The number of children attending pre-school nursery is estimated to have more than doubled from 88,000 on May 21 to 166,000 children on June 4, days after the June 1 reopening date set by the government.

Williamson said the figures showed that parents were increasingly reassured about sending their children back to school in safe conditions, saying it was “encouraging” to see so many pupils in the classroom again.

Under government plans, secondary schools will open from next week for Years 10 and 12, the years before GSCE and A-levels.

But Williamson left open the prospect that some pupils may not be back even after the summer break. “We will be working to bring all children back to school in September,” he said.

He dismissed calls to extend free school meal vouchers over the summer. “In terms of free school meals, we have never traditionally provided free school meals all through the summer. But what the DWP has been doing is putting an extra £6.5bn to support those families who are most vulnerable” 

The education secretary said that a ‘catch-up’ programme of support would be needed over the coming year.

“In terms of catch-up, this isn’t about something that is just over a few weeks. This has got to be an approach over a full year and more. That is what we are putting in place. That is how we are going to be supporting children into the long term.”

Teaching unions said they felt vindicated by the decision to ditch the move to reopening schools to all years before the summer

National Education Union joint general secretary Mary Bousted said: “Given the scale of the pandemic, schools were never going to be able to accommodate all their students with the current Government guidelines.”

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