Boris Johnson has abandoned advice that pupils should not wear face masks in English secondary schools.
The prime minister performed another U-turn in the face of growing pressure from headteachers, teaching unions and medical experts.
Face coverings will be mandatory in communal areas and corridors for children in towns and cities that are subject to stricter coronavirus restrictions.
But while headteachers will retain discretion over the use of face masks in schools in other parts of England, the government will drop guidance that they should not be used.
Speaking to Sky News on Tuesday night, Education Secretary Gavin Williamson said the climbdown was due to the government “listening” to a change in advice from the the World Health Organisation – despite that shift happening four days ago.
The WHO issued new guidance on 21 August, saying “children aged 12 and over should wear a mask under the same conditions as adults, in particular when they cannot guarantee at least a one-metre distance from others and there is widespread transmission in the area”.
Mr Williamson said: “We always follow and listen to the best scientific and medical advice, and that’s why we’re not recommending that face coverings should be mandatory right across the country in all schools.
“Because the best scientific and medical advice says that isn’t necessary.”
The education secretary described the new advice as an “extra precautionary measure” to prevent the transmission of coronavirus in some schools.
The UK government’s change in advice came late on Tuesday – hours after the Scottish government recommended the wearing of face masks in secondary school corridors, and the Welsh government said it was reviewing its advice on face coverings for pupils.
Meanwhile, Northern Ireland updated its guidance on face coverings to recommend they be worn by teachers and pupils in corridors and other communal areas of all secondary schools.