As schools across the UK reopen after the Christmas break, face masks have again been made mandatory in classrooms.
Pupils are also being asked to take part in onsite testing.
Until now, England was the only one of the four UK nations where face masks were not recommended for pupils in classrooms.
READ MORE: Boris Johnson announces how long Plan B restrictions could last
Staff absences and rising covid rates, caused by the rapid spread of Omicron, have led to fears of further disruption to education.
Education Secretary Nadhim Zahawi said face coverings would be required until January 26.
Teachers will not have to wear them under the new guidelines.
When asked today, the Prime Minister said face masks in schools will "not last a day more" than needed.
Conservative former minister Robert Jenrick said masks for pupils are "not cost-free" and do "affect the quality of teaching and the well-being of our children".
He asked in the Commons: "What assurances can (Mr Johnson) give me and parents across the country that this measure will be constantly reviewed and will only last as long as absolutely necessary?
Mr Johnson replied: "I can give him the categorical assurance that masks in schools will not last a day more than we need them."
Receive newsletters with the latest news, sport and what's on updates from the Liverpool ECHO by signing up here
