Prime Minister Boris Johnson addressed the nation this evening outlining the new restrictions, which are broadly equivalent to the national lockdown rules which were introduced last month.
The new tougher measures come into force at midnight tonight.
They apply to all areas currently under Tier 3 restrictions.
This means Hastings and Rother will fall under Tier 4.
It means people living in Tier 4 must not leave their areas.
Non-essential retail and indoor gyms must also close. People must also stay at home with limited exceptions.
Communal worship can continue, Mr Johnson said.
People should also work from home when they can.
People from other parts of the UK also must not enter Tier 4 areas.
Christmas bubbles for those living in Tiers 1 to 3 will not be able to include anyone in Tier 4.
In Tier 4, people are not permitted to mix with anyone outside their own household, apart from support bubbles.
Those living in Tier 4 areas are also not permitted to travel abroad, the Prime Minister announced this evening.
The rest of East and West Sussex, including Brighton and Hove will remain in Tier 2.
The restrictions will be reviewed on December 30.
Mr Johnson said: “We cannot continue Christmas as planned.”
He added that the spread of the virus in London and the South East was being driven by the new variant of Covid-19.
The Prime Minister reiterated, however, that there is no evidence that it causes more severe illness or higher mortality.
Mr Johnson said: “It may be up to 70 per cent more transmissible than the old variant.”
The Government’s chief scientific adviser, Sir Patrick Vallance, said the new Covid-19 variant was first seen in mid-September in London and Kent and by this month had become the ‘dominant’ variant in London.
Hastings and Rother had been placed under tougher Tier 3 restrictions from today due to rising infection rates following an announcement by Health Secretary Matt Hancock on Thursday (December 17).
The rest of East Sussex and West Sussex, together with Brighton and Hove, were kept under Tier 2.
London was placed in Tier 3 earlier this week.
Ahead of this evening’s announcement, Chief Medical Officer for England, Professor Chris Whitty said: “As announced on Monday, the UK has identified a new variant of Covid-19 through Public Health England’s genomic surveillance.
“As a result of the rapid spread of the new variant, preliminary modelling data and rapidly rising incidence rates in the South East, the New and Emerging Respiratory Virus Threats Advisory Group (NERVTAG) now consider that the new strain can spread more quickly.
“We have alerted the World Health Organisation and are continuing to analyse the available data to improve our understanding.
“There is no current evidence to suggest the new strain causes a higher mortality rate or that it affects vaccines and treatments although urgent work is underway to confirm this.
“Given this latest development it is now more vital than ever that the public continue to take action in their area to reduce transmission.”
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