BRITS across the country will only be able to meet one person outside their household as a gruelling new lockdown begins.
And we'll be limited to just one exercise session a day outdoors under the strict new rules.
⚠️ Read our coronavirus live blog for the latest news & updates
Visiting loved ones in their homes - or even gardens - is now banned under the new rule to control the spread of a mutant new strain of Covid.
Instead, people in England will only be able to meet one other person in a public space outside to exercise - meaning even perching on a park bench to chat with a pal isn't allowed.
The only exceptions are for support and childcare bubbles, for children whose parents have separated, and for those who provide care to disabled or vulnerable people.
Only single households and parents living alone with children under the age of 13 are allowed to form a support bubble.
Government documents released tonight also confirm that we're limited to just one exercise session in the local area per day.
Rules come into effect for England at midnight on Wednesday, the PM said, although Brits must start following them now.
It's thought the strict measures will be in place until mid-February.
In a sombre address tonight, Mr Johnson said: "With most of country already under extreme measures, it's clear we need to do more together to bring the virus under control while vaccines are rolled out."
It comes after the number of people testing positive for Covid explodes across England and a mutant strain takes hold in all regions.
The country's case rate is around three times higher than it was on December 1 as the mutation bites down in every area.
Mr Johnson said a national lockdown "tough enough to contain the variant" is needed.
"We are once again instructing you to stay at home, and only leave for limited reasons permitted in law, for example, shopping for essentials, work if you cannot work from home, exercise, to seek medical assistance or to escape abuse," he said.
Millions of people living in Tier 3 areas have previously been able to meet in groups of up to six outside.
But under the new lockdown, the whole country will face strict Tier 4 rules - including to stay at home.
Nicola Sturgeon this afternoon announced similar measures in Scotland.
Under the new rules, which come into force at midnight, Scots will be ordered to stay at home and schools will remain closed to pupils until February.
Outdoor gatherings will also be cut back, with people only allowed to meet one person from one other household.
The news marks a grim return to spring last year, when Brits hunkered down as the virus tore through the UK.
Boris Johnson tonight announced the return of a March-style lockdown for the country after the number of people testing positive for Covid surged by 50 per cent week-on-week.
Parliament will be recalled today to sit on Wednesday - meaning there will be a vote on the national measures.
However, the lockdown will be imposed imminently, with MPs given a retrospective say.
Meanwhile, the Covid threat level may about to be raised to five - the top level of warnings and the first time it's been this number.
Grave warning over mutatant virus
Experts have warned the super-infectious new coronavirus strain was spreading quickly among children DURING November lockdown
Academics from Imperial College London say the mutated super-infectious strain of Covid was spreading among children during the lockdown in November.
And they've warned that only closing schools can keep it contained.
Their study confirms that the new variant is more infectious, and the shutdown did little to contain it.
It was most prevalent among the 10-19 age group, and may be nearly 50 percent more transmissible, experts say.
The study is yet to be peer-reviewed, but academics claim the R number for the mutation is between 0.4 and 0.7 points higher.
On Sunday, Sage member Professor Sir Mark Walport said it was "pretty clear" tougher restrictions were needed to control the strain.
The former chief scientific adviser told the BBC's Andrew Marr Show: "It's the Tier 4 restrictions, it's obeying them.
"It is thinking about breaking essentially every possible route of transmission we possibly can.
"Those are the things that are absolutely necessary and it is pretty clear we're going to need more."
He said the mutation is "transmitted more readily in younger age groups", adding: "It is going to be very difficult to keep it under control without much tighter social restrictions."
This means there is a risk the NHS will become overwhelmed - and people should stick to extreme social distancing.
The PM this morning admitted we face a "tough" few weeks in the battle against the deadly bug,
In his first national interview wearing a mask, he said: "If you look at the numbers there's no question we will have to take tougher measures and we will be announcing those in due course."
Labour leader Keir Starmer has previously demanded all schools shut under a new national shutdown with the virus raging "out of control".
He said: "The more we delay, the worse it will get.
Most read in News
"The longer we delay, the longer schools will be closed for."
READ MORE SUN STORIES
The Government has so far resisted calls for a so-called 'Tier 5', which would feature even tougher measures - possibly including a curfew and restrictions on outdoor exercise.
But under the new shutdown, schools will close, non-essential shops will be shuttered and most travel is banned - similar to the first lockdown imposed in March.