Schools will remain open despite the threat of Omicron and will only close if there is an “absolute public health emergency”, Downing Street has said.
Earlier, Health Secretary Sajid Javid said he could not guarantee schools would stay open with Omicron spreading quickly across the country.
But Number 10 has now warned local authorities against deciding to close schools early for Christmas as a precautionary measure.
“There are certainly no plans to put in any restriction on schooling,” the prime minister’s official spokesman said.
“We’ve always sought to keep face-to-face schooling open and have only restricted it in when there’s the direst public health emergency.
“There’s certainly no plans to do that. We think we’ve got the right balance through Plan B and our big uptick in boosters.”
Asked whether schools might shut early for Christmas, the spokesman said: “Certainly we do not think anyone should be closing schools early unless they have received advice from the local director of public health that it’s necessary on public health grounds.
“We wouldn’t want to see that happening routinely, just as a precaution, because as I’ve said, education is vital.”
The NASUWT union representing teachers has called for a staggered return of pupils to schools and colleges in January, as well as additional on-site testing facilities up until the February half-term.
It added that the government should publish further guidance advising schools and colleges to cancel or postpone non-essential activities or events, as well as move to online staff and parental meetings.
In a letter to Education Secretary Nadhim Zahawi about the Omicron variant, Dr Patrick Roach, general secretary of the NASUWT, said: “I must urge you now to consider the immediate introduction of additional education measures to help slow the spread of COVID-19 and to minimise further disruption to education.”
He added: “The NASUWT urges the government to act immediately and to not delay critical decisions until the commencement of the school and college holiday period.”
It comes as a school leaders’ union has warned that delaying action until booster jabs take hold may keep children away from the classroom “longer” in the long term.
Mr Whiteman, general secretary of the NAHT school leaders’ union, said: “It is already chaos in some schools as the Omicron wave hits.
“Delaying action until vaccination can take hold may actually keep children away from school longer in the long term.”
After the Christmas holidays last year, Prime Minister Boris Johnson told parents on Sunday 3 January to send their primary-age children back to school.
But on the evening of the next day, he announced a national lockdown for England – with all schools closed to the majority of pupils.
Asked on LBC whether further school closures remained a possibility, Mr Javid said: “I don’t want to see that or any of these kinds of measures. I’m just going to focus on everything else we need to be doing, especially the booster programme.”
He added: “I’d say this, if you are asking me for guarantees, I will just say – as the health secretary, of course, I’m not the education secretary – that there are, when it comes to our fight against this pandemic, there are no guarantees.”
It comes after Mr Zahawi said he could not guarantee that in January all schools would be open everywhere.