Two cases of the Omicron coronavirus variant have been detected in Britain, the UK health secretary has said.
Sajid Javid said there would be targeted testing in Chelmsford and in Nottingham where the cases were found.
Boris Johnson will set out further measures in a Downing Street press conference on Saturday afternoon
Javid said: “Thanks to our world class genomic sequencing we have been made aware of two UK cases of the Omicron variant.
“We have moved rapidly and the individuals are self-isolating while contact tracing is ongoing.
“We will do all we can to protect the UK public against this emerging threat and that is why we are surging testing capacity to the impacted communities and introducing travel restrictions on a further four countries: Malawi, Mozambique, Zambia and Angola. We will not hesitate to take further action if required.
“This is a stark reminder that we are not yet out of this pandemic.
“Getting the vaccine has never been more important – please come forward for your first jab if you haven’t already and if eligible, book your booster as soon as possible.”
The Department of Health & Social Care said: “The UK Health Security Agency is carrying out targeted testing at locations where the positive cases were likely to have been infectious.
“In response to the developing situation, the UK is taking decisive action to protect public health.
“Confirmed cases and contacts are being followed up and requested to isolate and get tested as necessary.”