Students in secondary schools and colleges will have to continue to wear face masks in classrooms into the summer term, the government has said.
The Department for Education (DfE) said the "precautionary measure" – which has been in place since schools reopened in England on 8 March – would continue after the Easter holidays.
The announcement follows a review of the evidence on the use of face coverings in schools and colleges, including data from Public Health England.
However, the DfE also said that it expected face coverings would no longer be required to be worn by students in classrooms or other communal areas from 17 May.
This is the date Prime Minister Boris Johnson has pencilled in for step three of his roadmap for easing lockdown restrictions, which will see pubs and restaurants allowed to serve people inside and large events return.
Schools have been promised one week’s notice before any future changes to face mask guidance, while all other COVID measures will remain in place – such as regular asymptomatic testing and group bubbles.
The UK’s largest union, UNISON, welcomed the decision and said ministers "sensibly" listened to school staff.
"Keeping staff, pupils and their families safe and stopping wider infection spread is the most important thing. Any further decisions must be made according to the infection data, rather than dates," UNISON’s head of education Jon Richards said.
But the Us for Them children’s campaign group said it is consulting its lawyers over the move because there was "still no harm assessment and no evidence of the promised review".
Education Secretary Gavin Williamson said: "The return to school and college from 8 March has been an incredible success and I would like to thank staff, parents and pupils for their compliance with the guidance on reducing transmission of the virus.
"Our latest data also showed that attendance in school remains higher than at any point during the autumn term.
"On top of the protective measures previously in place such as regular handwashing and ventilation, we introduced face coverings in the classroom for secondary schools and colleges to help reduce transmission in parallel with the introduction of twice-weekly testing.
"Schools and students have done a great job adapting to COVID secure guidance and working hard to make sure it doesn’t impact learning.
"We obviously all want to get back to face mask-free classrooms and we will do this in line with the latest scientific data while balancing the interests of students, teachers and the wider community."
In March – when the government introduced the requirement for secondary school and college pupils to wear face coverings during indoor lessons when social distancing cannot be maintained – the DfE promised to review the "temporary measure" at Easter in collaboration with health experts.
Professor John Simpson of Public Health England said: "The return to school after Easter will allow us to continue monitoring the impacts of measures to reduce the spread of COVID, as we encourage families to test regularly.
"Wearing face coverings in secondary schools is an extra control measure to reduce the risk of transmission to support children continuing their education in the classroom."