The Prime Minister warned the coming weeks would be the “hardest yet” amid surging cases and patient numbers and said the lockdown was expected to last until mid-February.
In his address to the nation, Mr Johnson said: “Our hospitals are under more pressure from Covid than at any time since the start of the pandemic.
”In England alone, the number of Covid patients has increased by nearly a third in the last week to almost 27,000. That number is 40 per cent higher than the first peak in April.”
He said that across the UK, a record number of people tested positive for coronavirus on December 29 – around 80,000 people.
Boris Johnson announces new national lockdown in England
Mr Johnson said that over the last week the number of deaths was up 20 per cent over the last week and “will sadly rise further”.
Tthe UK’s chief medical officers raised the Covid-19 alert level to five – its highest – meaning “transmission is high or rising exponentially” and “there is a material risk of healthcare services being overwhelmed”.
The alert level has not been at level five before.
It indicates a risk of healthcare services being overwhelmed within 21 days without urgent action – it does not mean the NHS will be overwhelmed in three weeks, but there is a risk of that happening if no action was taken.
Dr Chaand Nagpaul, BMA council chair, said: “It’s clear that we need a major intervention to bring down the spread of this virus, especially the new more aggressive variant, given that the NHS in on the brink – currently facing exponential demand for care beyond what can be supplied in many places.
“Hospitals are stretched to breaking point, with doctors reporting unbearable workloads as they take on more Covid-19 admissions alongside the growing backlog of people who need other, non-Covid care.
“Doctors are desperate, with some even comparing their working environment to a warzone as wards overflow, waiting lists grow, and ambulances queue outside hospitals because there are now so many people with Covid-19.
“As a result, the NHS is currently facing a perfect storm of immense workload and staff burnout and more cases expected as we see the impact of Christmas on infection rates.
“The vaccination of healthcare workers needs to be significantly sped up so that health and care staff across the country are prioritised to receive both the first and second doses of the Covid-19 vaccine to help keep them free of the virus, so they can continue to provide the care so vitally needed by so many.”
Data provided by Number 10 show that there are currently 26,626 Covid patients in hospital in England – a rise of 30 per cent compared to the same day one week before – so a 30 per cent increase in a single week.
The peak of admissions in the first wave of Coronavirus was 18,974 on April 12, 2020.
Across the UK there were 80,664 positive tests in a single day on December 29. And further 65,571 on December 30.
And the latest case rate in England was 518 per 100,000 – three times the level at the start of December when it was 151.3 per 100,000.
NHS Providers chief executive Chris Hopson said patients were being admitted to hospital at an “alarming rate”.
“The announcement this evening is the only option to save lives, reduce patient harm and ensure the NHS can safely provide all patients with the care they need,” he said.
“Trust leaders are well aware that there is a cost and an impact of tighter restrictions, but they need these measures in place to stem the rapidly rising rate of infections, hospital admissions and deaths.
“Today has seen another steep rise in the number of Covid cases and the number of patients being admitted to hospital is also rising at an alarming rate.
“There are almost 9,000 more Covid patients in hospital beds – the equivalent of nearly 18 hospitals – than there was on Christmas Day, just 10 days ago. We know that number is going to continue to rise over the next few weeks.
“The lockdown announcement will help, but only if everyone follows the rules.
“As the prime minister indicated, the roll out of the Oxford/AstraZeneca vaccine does mean there is an end in sight and the NHS is working tirelessly to deliver the largest ever vaccination programme in history.
“But, for now, the NHS needs the public to play its part and stay at home.”
Danny Mortimer, chief executive of the NHS Confederation, added: “With huge pressure being placed on the NHS across the country in this last fortnight, and with the NHS’s capacity being confirmed as being at risk of becoming overwhelmed within the next 21 days, there was no option other than to take these drastic steps.
“The public must help the NHS by following the requirements of social distancing to the letter: the virus is not under control and the standards upon which the NHS prides itself are already being weakened and compromised.
“The Government must only relax these restrictions when it is absolutely safe to do so.”