Two linked cases of the new Omicron coronavirus variant have been detected in Britain connected to travel to southern Africa, health minister Sajid Javid said on Saturday.
"Late last night I was contacted by the UK Health Security Agency. I was informed that they have detected two cases of this new variant, Omicron, in the United Kingdom. One in Chelmsford, the other in Nottingham," he said in a broadcast clip.
The two individuals and all members of their households are being re-tested and told to self-isolate while further testing and contact tracing is done, the health ministry said.
England will also add Malawi, Mozambique, Zambia and Angola to its travel "red list" from 0400 GMT on Sunday, meaning British and Irish residents who arrive in the country must quarantine in a government-approved hotel for 10 days. Non-residents will be refused entry.
That list already contained Botswana, Eswatini, Lesotho, Namibia, South Africa and Zimbabwe.
Prime Minister Boris Johnson and the Chief Scientific Adviser Patrick Vallance and Chief Medical Officer Chris Whitty will hold a news conference later on Saturday "to set out further measures", Javid said.