New restrictions are coming into force today in Wales, Scotland and Northern Ireland in a bid to curb rising coronavirus cases.
Further rules have not been announced in England, with Boris Johnson saying before Christmas that the data is being monitored but as yet does not justify stricter measures. It is understood school closures are not being considered for January.
Here is what is happening across the rest of the UK.
Nightclubs will close and a maximum of six people will be allowed to meet in pubs, restaurants and cinemas.
Up to 30 people will be allowed at indoor events, while at outdoor events the limit is 50.
Social distancing of two metres required in public places and offices.
The rules take effect from 6am.
Social distancing of one metre will be required at large events from 5am and attendance will be limited to 100 people at indoor events where people are standing, or 200 for seated events inside.
For outdoor events, the limit is 500 people.
From 5am on Monday, nightclubs will be forced to close for three weeks, table service will be required in settings where alcohol is being served – and the one-metre rule will apply to hospitality and leisure settings.
Nightclubs will be shut, while indoor standing events and dancing in hospitality settings will be banned.
The measures begin at 6am.
From Monday, a limit of six people – or 10 people from a single household – will be allowed in indoor hospitality settings.
Children will not be counted in the total and weddings or civil partnership celebrations will be exempt.
It will be “strongly recommended” that household mixing should be reduced to a maximum of three households, while businesses are being told to take “reasonable measures” to implement two-metre social distancing in office spaces.
Working from home will be “strongly” advised where possible.
No 10 has not ruled out the possibility that ministers could meet on Monday to discuss the potential for new measures.
It is understood that a COVID-19 operations (COVID O) meeting has not yet been scheduled because ministers are waiting for more data.
Commenting on whether schools could close in January, a source close to Education Secretary Nadhim Zahawi said: “The PM and Nadhim are fully committed to keeping schools open, and there’s a shared commitment across government to do so.
“Education is a top priority and school closures are not something being considered.”
The government could choose to issue new voluntary guidance on limiting contacts to avoid the possibility of another damaging Tory rebellion, by recalling Parliament to approve new rules.
NHS national medical director Professor Stephen Powis is urging the public to get their booster jabs, saying “there is no time to lose”.
New rules in Europe
Elsewhere, some European countries have also brought in new restrictions.
In Belgium, indoor venues such as cinemas, theatres and concert halls will be closed, while sports fans will not be allowed into stadiums.
No indoor activities will be allowed except for museum visits, exercise, weddings and funerals.
A two-person limit will be set for shopping.
Bars and nightclubs were shut in Portugal on Christmas Day and working from home was made mandatory until 9 January.
Outdoor gatherings will be limited to 10 people per group on New Year’s Eve.