Prime Minister Boris Johnson has said it will be compulsory for children to return to school in September this year.
Mr Johnson admitted that schools being shut since March with the majority of pupils being taught online had been a "massive problem".
Speaking to the Mail on Sunday, the PM said: "We need to get the kids back into school. I want all pupils back in school in September."
Asked whether it would be compulsory, Mr Johnson replied: "Yes. It’s the law."
He addressed teaching unions who had opposed the wider reopening of schools over safety risks, saying they should "take their responsibilities seriously".
In a message to the unions, Mr Johnson said: "It’s the kids from the poorer families who aren’t going back, and so you are entrenching social injustice."
The Prime Minister's confirmation comes after the Education Secretary last week promised to get children back to school by September.
Gavin Williamson said they will achieve this by doubling the 15-students limit on class sizes in primary schools, and by ditching requirements for teachers to enforce the new ‘one metre plus’ social distancing measure - which comes into force from July 4.
Mr Williamson has faced wide criticism over his U-turn to get all primary schoolchildren back to the classroom for four weeks before the end of the summer term, which was the initial plan set out by the government.
However these rules apply only to England, as education is devolved by the separate governments in Wales, Scotland, and Northern Ireland.
