Covid live: fury after video about No 10 Christmas party emerges; early signs Omicron more transmissible

Early indications Omicron more transmissible than Delta, says Boris Johnson; Nicola Sturgeon says staff should work from home until mid-January

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All international arrivals to the UK are now required to take a pre-departure Covid-19 test to tackle the new Omicron variant.

The tightened requirements have just come into force from 4am (GMT) on Tuesday 7 December.