The prime minister has announced a full lockdown – including the closure of schools – will come into place across England in the coming days following fears the NHS could be overwhelmed by a surge in coronavirus cases.
The latest lockdown measures, which are similar to the tier-4 lockdown restrictions, will see pubs, restaurants and non-essential retail stores closed across the country, with only take away and food deliveries allowed.
Speaking from Downing Street, Boris Johnson said the measures were being implemented because of a rise in cases triggered by the more infectious variant of the virus that was identified late last year.
"With most of the country already under extreme measures, it is clear that we need to do more, together, to bring this new variant under control while our vaccines are rolled out," he said.
"In England, we must therefore go into a national lockdown which is tough enough to contain this variant.
"That means the government is once again instructing you to stay at home."
People will also be asked to work from home unless it is impossible to do otherwise, meaning construction and key workers can continue to attend work.
Meanwhile, all primary and secondary schools, as well as colleges, will also close from today and will move to remote learning, apart from for vulnerable children or children of key workers.
University students will also be unable to attend campuses and will be asked to move to online learning until mid-February. Face-to-face teaching will only be allowed for some specialist courses, such as medicine.
"We recognise this will mean that it is not possible or fair for all exams to go ahead this summer as normal," the prime minister said in the televised address last night.
"The education secretary will work with Ofqual to put in place alternative arrangements. We will provide extra support to ensure pupils entitled to free school meals with continue to receive them while schools are closed."
Under the new rules, people will be asked to stay at home as much as possible, only leaving to shop for essential goods, attend medical appointments or exercise near their home.
Unlike the spring lockdown, the government has said people will still be able to meet with one person from another household to exercise with outdoors but that tennis courts, golf courses and outdoor gyms will be shut.
The announcement came after the chief medical officers of England, Scotland, Wales and Northern Ireland met earlier today to raise the UK's coronavirus alert level from 4 to 5, its highest level. The alert level, which is distinct from the tiering system, describes how the pandemic is impacting the country. Level 5 means there is a "material risk of healthcare services being overwhelmed" within 21 days unless stricter action is taken.
Johnson said he hoped the restrictions would allow for a major roll out of the Covid vaccine, saying the NHS hoped to vaccinate care home residents and carers, frontline medical staff and the over-70s by mid-February.
"If we succeed in vaccinating all those groups, we will have removed huge numbers of people from the path of the virus. And of course, that will eventually enable us to lift many of the restrictions we have endured for so long," he said.
"I want to say to everyone, right across the UK, that I know how tough this is. And I know how frustrated you are and I know you've had more than enough of government guidance about defeating this virus, but now, more than ever, we must pull together."
He added: "The weeks ahead will be the hardest yet, but I really do believe that we are entering the last phase of the struggle, because for every jab that goes into our arms, we are tilting the odds against Covid, and in favour of the British people.
"And thanks to the miracle of science, not only is the end in sight, but we know exactly how we will get there.
"But for now, I am afraid, you must once again stay at home, protect the NHS, and save lives."
It is expected that MPs will vote on the new measures on Wednesday after the government announced they were recalling the Commons following the change.
But the PM urged people to follow the rules from last night and not to wait for the new rules to be passed into law
It is understood Johnson was prompted into the tough new action after new figures showed hospitalisations in England hit 26,626 on Monday, an increase of more than 30% on the same day last week.
Meanwhile, several hospitals in London and Kent have been forced to declare major incidents in recent days due to the increasing number of patients requiring critical care.
Responding to the announcement, Labour leader Sir Keir Starmer said the lockdown was "sadly necessary" and would be supported by his party.
"It is very important people heed the government guidance, particularly the stay at home message.
"So, whatever quarrels or challenges I have with the government and the prime minister, in a sense tonight, the really important thing to say is that we support these measures, and we are all under a duty to make them work."
Liberal Democrat leader Ed Davey said: "This is the public health policy the prime minister should have annoucned before Christmas, but yet again, Boris Johnson ducked the difficult decisions, failed to listen to experts and acted too late.
"Just yesterday morning Johnson was telling parents that schools were safe and children should definitely go. Today he is telling us that they must all move to remote learning but without any proper future plan."