The cases – in Brentwood, Essex, and in Nottingham – are “linked” and have been traced to southern Africa, health secretary Sajid Javid said, as he started targeted sequence testing of other cases in the areas.
Mr Javid announced that four countries – Angola, Mozambique, Malawi, and Zambia – are being added to the travel ‘red list’ from Sunday, requiring arrivals to quarantine in a hotel for 10 days.
“We’ve been always very clear that we will not hesitate to take further action if that is what is required,” he said.
“The two individuals concerned are isolating alongside their whole households, whilst further tests and sequencing is carried out.”
Scientists had predicted that the arrival of Omicron in the UK was inevitable – prompting some calls for the government to trigger its ‘plan B’ list of tougher Covid measures.
Asked if the public should now expect changes “as we head in into Christmas”, Mr Javid said: “We’ve always been really clear that we will do whatever is necessary to protect the progress that we’ve made as a country.
“We’ve come a long way, especially since the summer, and we keep all of this under review and if we need to take further action, we will.”
Boris Johnson will host a press conference with the chief medical officer and the chief scientific adviser later, “to set out further measures,” Mr Javid said.
“If anyone is sitting at home, thinking what can I do – get vaccinated,” the health secretary said, when asked what the public’s response should be.
Professor Chris Whitty, the chief medical office, said: “We will continue to work closely with the international community to quickly gather and analyse information on this variant to understand any possible increase in transmissibility or resistance to vaccines.”
On Friday, Mr Javid said the government would continue to resist pressure to introduce its plan B – mask-wearing, vaccine passports and working from home – for the time being.
And, earlier, two leading scientists expressed optimism that the worst predictions for the development of the new variant would not come to pass.
Professor Andrew Pollard, of the Oxford Vaccine Group, said it is “extremely unlikely” to trigger a major new wave of the Covid pandemic in the UK, despite the travel restrictions.
And the microbiologist Professor Calum Semple, who sits on the Sage advisory group, said the development was “not a disaster”.
‘The headlines from some of my colleagues saying ‘this is horrendous’ I think are hugely overstating the situation. Immunity from the vaccination is still likely to protect you from severe disease,” he said.
“You might get a snuffle or a headache or a filthy cold but your chance of coming into hospital or intensive care or sadly dying are greatly diminished by the vaccine and still will be going into the future.”
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