School nativity plays should go ahead and pupils should not be taken out of classes, Boris Johnson has said, despite announcing a raft of new measures to counter the spread of the omicron Covid variant.

       Speaking at a Downing Street press conference on Wednesday, the Prime Minister said that the doubling time for the number of omicron cases could be "between two and three days", and added that there was no indication yet that it is any less severe than previous strains.

       Mr Johnson announced that vaccine passports will now be mandatory for nightclubs and large events, and face masks will be required in most indoor public spaces from Friday, including theatres and cinemas. The Prime Minister also called on Britons to work from home where possible from Monday.

       However, he stressed that the new measures were "not a lockdown" and cautioned parents against taking their children out of school early.

       "We do not want kids to be taken out of school before the end of term, not that there is a very long time to go now. We do not want nativity plays to be cancelled," he said.

       "We think that it is OK currently, on what we can see, to keep going with Christmas parties. But everybody should exercise due caution; have ventilation, wash your hands, get a test before you go, give everybody at the party confidence they are going to be meeting someone who is not contagious."

       Will schools close early?

       No. The Prime Minister insisted that he does not want to see schools close early for Christmas, and called on parents not to take their children out of lessons as a precaution. No updated guidance has been issued by the Department for Education.

       However, the UK’s largest teacher union has called on the Government to implement a Plan B for schools, including the return on bubbles and face masks in the classroom.

       The National Education Union (NEU) also urged ministers to step up self-isolation rules for children, as well as reintroduce one-way systems and staggered break times to reduce transmission.

       Kevin Courtney, the NEU's joint general secretary, said: "We are disappointed that in his announcement the Prime Minister has made no mention of schools, given that cases are rising so fast and this is leading to so much disruption of education.

       "More than 200,000 pupils were absent for Covid-related reasons on November 25 and since then infection rates among school-age children have risen further.

       "It is clear that current mitigations are not enough to keep at bay rising case counts, especially in the new context of the fast-spreading Omicron variant.

       "The National Education Union put out its own Plan B for schools earlier today, and we think Boris Johnson must act now to minimise the disruption of education."

       Will pupils have to wear face masks?

       The Government recommends that staff, adult visitors and pupils in Year 7 and above wear face masks when moving around educational premises and outside of classrooms, such as in corridors and communal areas.

       Pupils are also advised to wear face masks when travelling on public transport and dedicated school transport. However, the Government does not currently advise pupils and teachers to wear face masks inside the classroom.

       In primary schools, face masks are still recommended to be worn by staff and adults when moving around in corridors and communal areas, but not in classrooms. Children in primary schools are not advised to wear face coverings.

       Will bubbles return?

       The Government does not currently advise the re-implementation of bubbles in schools. This means that if a single pupil in a specific cohort tests positive for Covid, the entire class or year group does not need to be sent home to isolate.

       School assemblies, nativity plays, and break time mixing can still take place.

       However, the Government warns that schools should ensure that contingency plans cover the possibility that it may become necessary to reintroduce bubbles for a temporary period in order to reduce mixing between groups.

       "And decision to recommend the reintroduction of bubbles would not be taken lightly and would need to take account of the detrimental impact they can have on the delivery of education," it says.

       Can children still go to school if their parents test positive?

       All individuals who have been identified as a close contact of a suspected or confirmed case only of the omicron variant will be required to self-isolate immediately, regardless of vaccination status and age.

       Further actions may also be taken in schools by a local incident management team investigating suspected cases of omicron.

       But for all other pupils, isolation rules remain unchanged. Children are not required to self-isolate if they live in the same household as someone with Covid, as long as they are not a suspected or confirmed case of omicron. They are instead urged to take PCR tests to confirm their Covid status.

       This article is being kept updated with the latest news and Government guidance daily.