Professor Chris Whitty has warned a new Covid strain could be worse than Omicron as Boris Johnson cautioned Britain cannot "declare victory" over the virus yet.
Speaking at a Downing Street press conference, England's Chief Medical Officer said a new variant could also be "more vaccine-escaping" than the current dominant strain.
Speaking after he announced all remaining Covid restrictions will be axed, the PM said there "may be significant resurgences" and "it's very possible that those will be worse than Omicron".