The plan for all elementary school years in England to return to school before the end of the term has to be abandoned by the government.
The goal was for all elementary students to spend four weeks in school before the summer vacation.
But it is no longer thought to be feasible and, instead, schools will have the “flexibility” to admit or not to admit more students.
School heads said this had never been a practical possibility.
It comes after Health Secretary Matt Hancock admitted at the Downing Street briefing on Monday that secondary schools in England may not fully reopen until September “at the earliest.”
Prime Minister Boris Johnson will later chair a cabinet meeting to discuss next steps to ease lock restrictions before Education Secretary Gavin Williamson makes a statement in the House of Commons on the reopening of schools .
There are separate rules for managing the coronavirus threat in England, Wales, Scotland and Northern Ireland.
Children in England began to return to primary schools in a multi-phase process last week, with reception, first and sixth grade students first.
Williamson will later give an indication of the number of more pupils in England who have returned, but he should also say that primary schools will no longer have to prepare for the return of all pupils, as previously proposed by the government .
Instead, schools will have the opportunity to increase their numbers – but it will be up to them to decide if they can bring more classes and to remove the “pressure” to prepare.
The announcement will mean that many children from these other groups will not return to school until September.
Several weeks ago, school heads warned that it was not a realistic possibility to accommodate all primary groups at the same time, as social distancing limited their capacity.
Class sizes are now 15 students or less – so if each class occupied two classrooms, principals argued that they would not have space for all groups of the year.
“The ambition to bring back all the elementary school groups for a month before the end of the summer term was a case where the government had promised something that was not deliverable,” said Geoff Barton, chief of chiefs of ASCL establishment. union.
“It is not possible to do this while maintaining small classes and social bubbles, so we are not surprised that the policy has been abandoned,” he said.
Paul Whiteman of the National Association of Head Teachers said “we are pleased to see that the government will not force the impossible” and that the plan has too many “practical barriers”.
Schools remained open throughout the isolation for children of key workers and vulnerable children.
But last Monday, primary schools began to re-invite two million more children in three years.
High school students in grades 10 and 12 must start returning for certain school sessions starting June 15.
The number of primary school students is thought to have increased as parents became more confident – but there have also been local concerns about the different regional infection rates.
Teachers’ unions have warned that it is too early to return to school – and some local authorities have delayed return to school in their area.
But the Ministry of Education has argued that children must return to school – and that safety has been “paramount” in the plans to bring back more students.
Wales schools will reopen from 29 June for all age groups for limited periods during the week, while Scottish schools are scheduled to reopen at the start of the autumn term on 11 August, with a some home learning.
Some pupils from Northern Ireland preparing for the exams and those about to enter post-primary schools will return in late August, with a gradual return for the rest in September.
The UK recorded its smallest daily increase in the number of coronavirus deaths since before the lockdown on March 23, according to the latest government figures.
At 5:00 p.m. Sunday, 55 people died after being tested positive for the virus, bringing the total to 40,597.
There are generally fewer deaths reported on Monday – due to late reporting this weekend.
The figures came as a study estimated that the blockages had saved more than three million lives of the coronavirus in Europe.
Researchers at Imperial College London have used computer models to predict the spread of the virus if no restrictions had been put in place in 11 European countries, finding that the “death toll would have been huge” without locking in.
In the UK, the lockout prevented 470,000 deaths until May 4, the study found.