Addressing the nation tonight, earlier than anticipated due to leaks to the media, the Prime Minister warned the NHS was at risk of being overwhelmed, with deaths heading towards “several thousands” and the level of the first peak.
He said: "Now is the time to take action because there is no alternative."
Mr Johnson chaired Cabinet this afternoon where the new measures were agreed, before he spoke with Labour leader Sir Keir Starmer and Commons Speaker Sir Lindsay Hoyle.
He will head to the Commons on Monday to outline the measures and take questions from MPs, before a vote on the new rules on Wednesday ahead of them coming into force at 00.01am on Thursday.
Mr Johnson said: “I’m afraid no responsible Prime Minister can ignore the message of those figures.
“We know the cost of these restrictions – the impact on jobs and livelihoods, and people’s mental health. No-one wants to be imposing these measures.”
He said the overrunning of the NHS would be a “medical and moral disaster, beyond the raw loss of life”.
He said: “Doctors and nurses would be forced to choose which patients to treat, who would get oxygen and who wouldn’t, who would live and who would die.
“Doctors and nurses would be forced to choose between saving Covid patients and non-Covid patients.
“The sheer weight of Covid demand would mean depriving tens of thousands, if not hundreds of thousands, if not millions of non-Covid patients of the care they need.”
He added: “The risk is, for the first time in our lives, the NHS will not be there for us.”
The Prime Minister thanked people who had been “putting up with” local restrictions.
But he warned: “We’ve got to be humble in the face of nature… the virus is spreading even faster than the reasonable worst case scenario of our scientific advisers.
“Unless we act, we could see deaths in this country running at several thousand a day – a peak of mortality, alas, bigger than the one we saw in April.”
Mr Johnson insisted the new national lockdown is not the same as the “full scale lockdown” of the spring.
The Prime Minister told the Downing Street press conference: “We will get through this but we must act now to contain this autumn’s surge.
“We’re not going back to the full scale lockdown of March and April, the measures I’ve outlined are less restrictive.
“But I’m afraid from Thursday the basic message is the same: Stay at home, protect the NHS and save lives.”
Mr Johnson added: “I’m under no illusions about how difficult this will be for businesses which have already had to endure such hardship this year and I’m truly, truly sorry for that – and that’s why we’re going to extend the furlough system through November.
“The furlough system was a success in the spring, it supported people in businesses in a critical time. We will not end it, we will extend furlough until December.”
He said the measures would be time-limited from November 5 to December 2, when restrictions would be eased and regions would go back into the tiered system.
He added: “Christmas is going to be different this year, perhaps very different. but it’s my sincere hope and belief that by taking tough action now we can allow families across the country to be together.”
Labour leader Sir Keir welcomed the national lockdown for England but said it should have happened “weeks ago”, warning that the delay will cost lives and cause restrictions to last for longer.
He told reporters: “Everybody is concerned about the rise in infections, the hospital admissions and tragically the number of deaths. That’s why three weeks ago, I called for circuit-break.
“The Government completely rejected that only now to announce the self-same thing.
“Alas the delay now will cost, the lockdown will be longer, it’ll be harder and there’s a human cost which will be very, very real.
“Now, there’s no denying these measures are necessary and I’m glad that the Government has finally taken the decision that it should have taken weeks ago.”
Sir Keir indicated that Labour will back the Government in a Commons vote on the new lockdown, saying “these measures are necessary”, but warned against further delay.
Asked about the restrictions not coming into force until Thursday, the Labour leader told reporters that they should be brought in “swiftly”.
“The last thing we need is days before restrictions come in. If they’re necessary, they’re necessary now,” he added.
Ministers were told that the incidence rate for coronavirus was growing and that the NHS was under increasing pressure, with an average of one in 100 people having Covid-19.
On the current trajectory Government scientists on the Scientific Pandemic Influenza Group on Modelling (SPI-M) have assessed the NHS will reach its fixed and surge bed capacity during the first week in December, even after elective procedures are cancelled.
They said the growth in the virus is now national, and although worse in the North, it was spreading everywhere.
Chief Medical Officer Professor Chris Whitty told the press conference : “We now have several hospitals with more inpatients with Covid than we had during the peak in the spring.”
Prof Whitty added that “the death rate, although rising, is still significantly below the peak”.
But if numbers keep rising, “in terms of deaths over the winter, there’s the potential for this to be twice as bad, or more, compared to the first wave,” according to Chief Scientific Officer Sir Patrick Vallance.
Prof Whitty warned that the prevalence of coronavirus has been increasing “extremely rapidly” in recent weeks.
Citing Office for National Statistics data, the chief medical officer for England told the Downing Street press conference: “The prevalence of this disease has been going up extremely rapidly over the last few weeks, having been very flat due to the work of everybody in the country over spring and summer.
“And we now have around 50,000 new cases a day and that is rising.”
Under the measures announced tonight people can only leave home for specific reasons including for education, work if they cannot work from home, for exercise and recreation outdoors, for medical reasons, to escape injury or harm, to shop for food and essentials and to provide care for vulnerable people.
Schools, colleges, and universities are to remain open, and Mr Johnson added: “We cannot let this virus damage our children’s futures even more than it has already and I urge parents to keep taking their children to school and I’m extremely grateful to teachers across the country for their dedication in enabling schools to remain open.”
He also urged people to continue to use the NHS unless they were told not to by clinicians.
While individuals can also meet with one other person at a social distance in somewhere such as a park, but only if both people are solo.
And it is being urged that workplaces should stay open where people cannot work from home, for example in construction and manufacturing, however non-essential shops and leisure venues will all be closed, as will pubs, bars and restaurants.
Takeaway services and click and collect can continue, and support bubbles will remain intact.
And furlough will return at up to 80 per cent of pay for the duration of the national measures.
The introduction of national restrictions marks a dramatic shift in Government policy, as the Prime Minister has until now resisted pressure to reintroduce nationwide restrictions.
Members of the Government’s Scientific Advisory Group for Emergencies (Sage) have backed the introduction of more stringent measures.
Professor Sir Jeremy Farrar said the consequences of sticking with the current “insufficient” restrictions would be “much worse” than going for a second lockdown.
The director of the Wellcome Trust said: “The sooner we act, the sooner we can start to recover. It will be a very difficult few weeks now and no one can underestimate the toll that will take on people.
“But the consequences of sticking with the current insufficient restrictions would have been much worse.”
Sage member Professor Calum Semple told BBC Radio 4’s Today programme: “For the naysayers that don’t believe in a second wave, there is a second wave.
“And, unlike the first wave, where we had a national lockdown which protected huge swathes of society, this outbreak is now running riot across all age groups.”
Professor John Edmunds said the only way to have a “relatively safe” Christmas is to take “stringent” action now to bring the incidence of the virus “right down”.
It comes after a senior Government scientific adviser said it is “definitely too late to think that the two-week circuit-breaker on its own will sort this out”.
“It would bring it down a bit but it wouldn’t be enough to bring (the R value) right down. A two-week circuit-breaker would have an effect but now almost certainly it would need to go on for longer to have a significant effect.”
British Chambers of Commerce director general Adam Marshall described the new restrictions as “a devastating blow” to business communities.
Market confidence has been “hit hard by the unclear, stop-start approach” taken by governments across the UK during the pandemic.
He said: “Many firms are in a much weaker position now than at the start of the pandemic, making it far more challenging to survive extended closures or demand restrictions.”
He called for Government support for businesses facing hardship, whether through loss of demand or closure, to be boosted.
He said: “The Government must not squander the time afforded to them through another lockdown to enable mass testing and fix test and trace systems – which hold the key to a lasting exit strategy for both public health and the economy.”
Mr Johnson said “rapid turnaround” tests will be used to reduce the prevalence of the virus, and tests of “whole cities” and will be rolled out within days.
The Prime Minister said: “We now have the immediate prospect of using many millions of cheap, reliable and above all rapid turnaround tests.”
He said these will “drive down the disease”, the Army has been brought in to assist the logistics and a rollout will begin in a “matter of days”.
“Over next few days, weeks, we plan a steady but massive expansion in the deployment of these quick turnaround tests, applying them in an ever-growing number of situations from helping women to have their partners with them in labour wards when they’re giving birth, to testing whole towns and even whole cities,” he said.
TUC general secretary Frances O’Grady said: “The Government should have acted decisively much sooner and now families face a grim winter.
“The extension of the furlough scheme is long overdue and necessary, but ministers must do more to protect jobs and prevent poverty.
“Furlough pay must never fall below the national minimum wage. We need a boost to Universal Credit and Government should not abandon the self-employed. And we will not control the virus unless the Government fixes the test and trace system and the scandal of workers asked to self-isolate without decent sick pay.”
Unison general secretary Dave Prentis said: “It’s a difficult time but if everyone works together, we can slow the spread and stop hospitals being overwhelmed at this critical time.
“That also means ministers giving councils the resources they need to play their part.
“As well as protecting the NHS, lessons must be learned from the dire situation in the care sector earlier in the year. Proper support and protection are paramount. We can’t see a repeat of the heart-breaking death rates in care homes.
“A further lockdown isn’t something anyone wanted, but we have to save lives.”