Face coverings will be mandatory again in shops and on public transport in England from next week, the PM said, after two people were infected with the Covid variant, Omicron.
PCR tests for everyone entering the UK will be introduced and all contacts of new variant cases will have to self-isolate, even if fully jabbed.
Boris Johnson said Christmas would be "considerably better" than last year.
The measures were "temporary and precautionary", he added.
Mr Johnson announced the restrictions at a Downing Street news conference with the chief scientific adviser to the government, Sir Patrick Vallance, and the UK's chief medical officer Prof Chris Whitty.
Earlier it was confirmed that Omicron cases had been detected in Brentwood, Essex, and Nottingham. Officials said the cases were linked and connected to travel in southern Africa.
Countries around the world are currently racing to introduce travel bans and restrictions on southern African countries in an effort to contain the variant's spread.
https://www.bbc.co.uk/news/uk-59445124
PCR tests for everyone entering the UK will be introduced and all contacts of new variant cases will have to self-isolate, even if fully jabbed.
Boris Johnson said Christmas would be "considerably better" than last year.
The measures were "temporary and precautionary", he added.
Mr Johnson announced the restrictions at a Downing Street news conference with the chief scientific adviser to the government, Sir Patrick Vallance, and the UK's chief medical officer Prof Chris Whitty.
Earlier it was confirmed that Omicron cases had been detected in Brentwood, Essex, and Nottingham. Officials said the cases were linked and connected to travel in southern Africa.
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Countries around the world are currently racing to introduce travel bans and restrictions on southern African countries in an effort to contain the variant's spread.
https://www.bbc.co.uk/news/uk-59445124