Wearing masks in some public areas is poised to become mandatory again along with several other rules following the emergence of a new Covid strain. Named Omicron, the discovery of this new Covid variant this week has sparked concerns that cases could start to once again spiral out of control. Below, Express.co.uk explains what restrictions the Prime Minister will be introducing.
Key points:
Prime Minister Boris Johnson said today: "We're not going to stop people travelling, I want to stress that, we're not going to stop people travelling, but we will require anyone who enters the UK to take a PCR test by the end of the second day after their arrival and to self-isolate until they have a negative result.
"Second, we need to slow down the spread of this variant here in the UK, because measures at the border can only ever minimise and delay the arrival of a new variant rather than stop it all together.
"We will require all contacts of those who test positive with a suspected case of Omicron to self-isolate for 10 days regardless of your vaccination status.
"We will also go further in asking all of you to help contain the spread of this variant by tightening up the rules on face coverings in shops and on public transport."
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Masks will once again become mandatory for people to wear in shops and whilst on public transport. However, this measure does not extend to restaurants or bars.
On Thursday the UK announced that travellers from South Africa, Namibia, Zimbabwe, Botswana, Lesotho and Eswatini would not be able to enter the country unless they are UK or Irish nationals, or UK residents.
As of 4am on Sunday, Malawi, Mozambique, Zambia and Angola will also be added to that list.
The PM has also revealed tonight that anyone returning to the UK from anywhere abroad will now have to self-isolate until they have produced a negative PCR test result.
Lateral flow tests will no longer be accepted and have been dropped for international arrivals.
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Individuals who have been in contact with anyone who has returned a positive Covid test result will also now have to self-isolate regardless of their vaccination status. Under previous rules those who were fully vaccinated did not have to self-isolate so long as they did not develop symptoms.
In addition, the PM has asked the Joint Committee on Vaccination and Immunisation (JCVI) to review the current vaccine programme and investigate whether children under the age of 12 can receive the vaccine.
Mr Johnson has also asked whether booster jabs can be administered after five months instead of the current six month period.
At this moment the Government will not be introducing vaccine passports to gain entry to pubs or other public events.
The PM said the new measures will be reviewed in three weeks. However he was criticised for not going far enough with the rollout of the new rules as the UK will not see the full extent of Plan B.
Mr Johnson said: "When you look at Delta, the measures we had in place are effective in the sense you're seeing this downwards tracking of hospitalisations and deaths. That's the key take out its the best way to beat this is to get their booster."
He added that for tackling the Omicron strain, "you need to slow the seeding", saying that tough measures at the border will help "to give us time to give another 6 million boosters in people's arms."
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The World Health Organisation has warned against ‘overreaction’ to the new variant and urged the public to ‘stay calm’.
So as yet, it seems there is no need to have another lockdown. And as England's chief medical officer Professor Chris Whitty has said, Britons will likely not accept one anyway.
Speaking in a panel discussion hosted by the Local Government Association, he said he was concerned public appetite for a lockdown this close to Christmas would be low.
He said: "My greatest worry at the moment is that people... if we need to do something more muscular at some point, whether it's for the current new variant or at some later stage, can we still take people with us?"
But he added: "I think the extraordinary thing has been the ability of the UK population, with very, very small exceptions, to just accept that there are things we collectively have to do to protect one another and do collectively, including things that have been very destructive to social and economic situations for individuals and families,' he said.
"Obviously, we want to avoid having to do those at all if we can, and to do the minimum ones necessary, but will we be able to maintain public support? And I think my overall view is, I think we will."
On Wednesday, South Africa became the first country to report an official case of the Omicron variant to the World Health Organisation (WHO).
Early evidence of infection from the variant suggests that it contains many mutations and that there is a higher risk of reinfection.
In a statement, the UN public health body said: “This variant has a large number of mutations, some of which are concerning.” However, WHO officials have said it will take several weeks before they can understand the impact of the variant and how transmissible it is.
Mr Johnson said today: "This variant is spreading around the world. There are many things that we just cannot know at this early stage."
He added t is an "extensive mutation" that "might at least in part reduce the effectiveness of our vaccines" and that "targeted measures now" will "buy time for our scientists" to know what we are "dealing with".
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