BORIS Johnson has announced that new restrictions will be introduced in England to stop the spread of the Omicron Covid variant.

As part of the UK Government's "Plan B", people will be asked to work from home where possible from Monday and vaccine passports will be made mandatory at nightclubs and larger venues where crowds gather, Johnson announced at a press conference in Downing Street.

Mask rules are also to be extended to more public places like cinemas and theatres from Friday, December 10.

Johnson said the mask guidance would include exemptions for when eating, drinking, exercising or singing.

Tory MPs have already said that this announcement is a distraction from the scandal of parties in Downing Street that happened last Christmas.

Johnson said: “Employers should use the rest of the week to discuss working arrangements with their employees but from Monday you should work from home if you can.

“Go to work if you must but work from home if you can.

“I know this will be hard for many people but by reducing your contacts in the workplace, you will help slow transmission.”

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The Cabinet’s Covid-19 operations (Covid-O) committee had been expected to meet to consider the next steps amid widespread suggestions that the further measures would be announced as Downing Street faced intense pressure over an allegedly rule-breaking Christmas party in No 10 last year.

 Johnson said there was “no excuse” for the video showing No 10 aides joking about an alleged lockdown party, but that Allegra Stratton had been a “fine colleague”.

Johnson said: "We can’t yet assume that Omicron is less severe than previous variants.

“So while the picture may get better, and I sincerely hope that it will, we know that the remorseless logic of exponential growth could lead to a big rise in hospitalisations and therefore, sadly, in deaths.

“That’s why it is now the proportionate and the responsible thing to move to Plan B  in England while continuing to work closely with our colleagues in the devolved administrations, so we slow the spread of the virus, buy ourselves the time to get yet more boosters into arms, especially in the older and more vulnerable people.”

One reason for the rapid shift towards Plan B could be figures from the Scientific Advisory Group for Emergencies (Sage) panel which suggested at least 1,000 people a day may need hospital treatment for Omicron by the end of the year without restrictions.

Leaked minutes of a Sage meeting held on Tuesday said the Government should “urgently” consider the need for measures to reduce transmission of the virus and protect the NHS from “unsustainable pressure”, the BBC reported.

England’s chief medical officer Professor Chris Whitty said there was an “incredibly steep” increase in cases in South Africa, where Omicron was first detected, and “we are now seeing this translate into increases in hospitalisations”.

He said there was some data suggesting “around about a 300% increase in hospitalisations over the last week”.

Asked about the impact of the Downing Street party row on people following the rules, Whitty said: “We all know people get very angry, including colleagues and friends, when they feel that it’s unfair.”

He said that was “quite different from people wanting to actually know what’s going on and then make decisions”.

The peak of the Omicron wave is “highly likely to be higher” than 1000 to 2000 variant-related admissions per day without new rules, the document said.

Health Secretary Sajid Javid said Omicron cases could exceed 1 million by the end of this month on the current trajectory.

He said: “Although there are only 568 confirmed Omicron cases in the UK we know that the actual number of infections will be significantly higher.

“The UK health security agency estimates that the number of infections are approximately 20 times higher than the number of confirmed cases, and so the current number of infections is probably closer to 10,000.

“UKHSA also estimate that at the current observed doubling rate of between two and a half and three days, by the end of this month, infections could exceed 1 million.”

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When announcing the changes in the House of Commons, Javid was heckled by Tory MPs and William Wragg (Hazel Grove MP) was heard shouting "resign".

Wragg also previously described such a move to Plan B as a "diversionary tactic".

Wragg told the Commons: "There are media reports of a Cabinet meeting and press conference this afternoon to initiate Covid winter plan B without reference to this House."

Wragg went out to criticise the possible introduction of vaccine passports under the plan, before adding: "Is my Right Honorable friend the Prime Minister aware that very few will be convinced by this diversionary tactic?"

As Javid said the measures were not something ministers wanted to take, shouts of “rubbish” and “what a load of old tripe” could be heard in the chamber.

When he announced an extension of the legal requirement for face coverings, Labour MPs pointed at some Tory MPs who were not wearing them in the chamber.

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He said: "We take these steps with a heavy heart, but we do so confident that we’re doing everything in our power to keep our nation safe this winter.

“We’ve come so far over the course of this year thanks to the defences we’ve built against this deadly virus.

“Now, as we face this new threat, we must draw on the same spirit that has got us here, strengthening our defences and thinking about what we can do to help get this virus under control.”

Javid said the new restrictions will be reviewed on January 5, and that they will all end on January 26.

SNP spokesperson for public health Martyn Day said the announcement was “better late than never”.

He said: “I find myself in much agreement with what the Secretary of State has said, perhaps much more than many on his own benches.”

He said “lower immunity from vaccination is particularly worrying” and a “considerable concern”, adding it is still important for people to get vaccinated.

He said: “England’s plan B does remarkably resemble the current position in Scotland … so it’s better late than never.”

Vaccine passports have been in place in Scotland since October and face masks have continued to be mandatory in indoor public places while the mandate was removed in England earlier this year.

First Minister Nicola Sturgeon announced that people should work from home where possible yesterday as the Omicron variant spreads throughout UK nations.

Day asked how the Health Secretary thinks its acceptable “not to have held a Cobra meeting with the devolved governments when it has reached this point for the restrictions”.

Javid said he has regular meetings with his counterparts across the UK.