England will enter a third national lockdown from midnight.

In an address to the nation last night, Prime Minister Boris Johnson said: “I know how tough this is, and I know how frustrated you are and I know you have had more than enough of government guidance about defeating this virus, but now, more than ever, we must pull together.”

Schools will move to remote learning, and those clinically vulnerable will be asked to shield once again.

The measures are expected to continue until mid-February to prevent the NHS being overwhelmed by surging coronavirus infections.

What were the key points?

We're back to 'Stay at home, Protect the NHS and Save Lives'.

The Prime Minister said: “You may only leave home for limited reasons permitted in law, such as to shop for essentials, to work if you absolutely cannot work from home, to exercise, to seek medical assistance such as getting a Covid test, or to escape domestic abuse.”

The clinically extremely vulnerable are advised to begin shielding again, and Mr Johnson said those affected will receive letters “shortly”.

He advised people to visit gov.uk/coronavirus for the full details of what people can and cannot do.

What's happening with schools?

Primary and secondary schools will close immediately and move to online learning for all pupils except children of key workers and the most vulnerable, Mr Johnson said.

They will shut from today and move to remote learning. Exams are also cancelled this year and preparations are under way with exams regulator Ofqual in talks about how to proceed.

Early years settings such as nurseries and childminders can remain open, and existing childcare bubbles will be allowed to stay in place.

University students will not be allowed to return to campus and will be expected to study from their current residence.

In-person university teaching will only take place for a small number of critical courses.

When will it start? 

From midnight last night we are being urged to follow the rules. It will become law on Wednesday after going before Parliament.

How long will it last?

The measures are expected to be in place until mid-February.

What about exercise and work?

Exercise will be allowed – preferably limited to once a day – with members of your household or support bubble or one other person from another household, such as if going for a walk or run.

People will be able to go to work if it is impossible to work from home, such as those working in the construction sector or who are critical workers. All others must work from home.

Cleaners and other trades people will still be able to work in people’s homes.

How will it be enforced?

Police will have enforcement powers.

Churches can stay open

Places of worship can remain open for individual prayers and communal worship, but people should only visit with their household or support bubble.

Weddings, civil partnership ceremonies and funerals are allowed with strict limits on attendance.

What about shops? 

All non-essential shops, hairdressers and personal care venues must close.

Supermarkets, builders’ merchants and garden centres can stay open.

Restaurants and other hospitality venues can continue delivery or takeaway, but people will not be able to add alcohol to that order.

Those who shield should not go to work

Those who are clinically vulnerable and who were previously told to shield should stay at home and only leave for medical appointments and exercise.

They are advised not to go to work even if they cannot work from home.

Playgrounds will remain open

But outdoor gyms, tennis courts and golf courses must close, and outdoor team sports will not be permitted.

Premier League and other elite sports that already have in place strict testing regimes and their own bubbles will be allowed to continue.

Why is it happening?

The Prime Minister said that in England the number of Covid patients in hospitals has increased by nearly a third in the last week to almost 27,000 – some 40% higher than the first peak in April.

On December 29 “more than 80,000 people tested positive for Covid across the UK”, the number of deaths is up by 20% over the last week “and will sadly rise further”.

“With most of the country, or maybe under extreme measures, it’s clear that we need to do more together to bring this new variant under control while our vaccines are rolled out.

Ahead of the announcement, the UK’s chief medical officers recommended the Covid-19 alert level should be moved to five – the highest setting.

Parts of the health services across the UK are under “immense pressure”, the chief medical officers for England, Scotland, Wales and Northern Ireland, and NHS England’s national medical director Professor Stephen Powis said.

In a joint statement on Monday evening they said that due to rising cases and without further action there is a risk of the NHS “in several areas” being overwhelmed over the next 21 days.

They said: “Following advice from the Joint Biosecurity Centre and in the light of the most recent data, the four UK chief medical officers and NHS England medical director recommend that the UK alert level should move from Level 4 to Level 5.

“Many parts of the health systems in the four nations are already under immense pressure. There are currently very high rates of community transmission, with substantial numbers of Covid patients in hospitals and in intensive care.

“Cases are rising almost everywhere, in much of the country driven by the new more transmissible variant. We are not confident that the NHS can handle a further sustained rise in cases and without further action there is a material risk of the NHS in several areas being overwhelmed over the next 21 days.

“Although the NHS is under immense pressure, significant changes have been made so people can still receive lifesaving treatment. It is absolutely critical that people still come forward for emergency care. If you require non-urgent medical attention, please contact your GP or call NHS 111.”

Dorset Echo:

Are we in the same situation as March?

Mr Johnson said that the weeks ahead would be the “hardest yet” but added that he believed the country was entering “the last phase of the struggle”.

What else did he say? 

The Prime Minister said the new variant – which is 50% to 70% more transmissible – was spreading in a “frustrating and alarming” manner.

“As I speak to you tonight, our hospitals are under more pressure from Covid than at any time since the start of the pandemic,” he said.

What happens now?

Follow the rules and stay home as much as possible. Parliament will be recalled on Wednesday where MPs will vote on the new lockdown restrictions, something some MPs have been critical of in recent months.