Speaking on the Andrew Marr Show on BBC television, Hopkins said: "We have not got enough data about this variant yet to be able to clarify whether it's a variant of concern. We have put it as a variant under investigation."

"To escalate it up the ranking we need to know that it's increased transmissibility, increased severity, or vaccine-evading, and we just don't have that yet, but we're looking at the data on a daily basis."

PHE has said it has identified 77 cases of the variant in Britain.

Earlier, environment minister George Eustice said Prime Minister Boris Johnson's trip to India later this month should go ahead despite rising cases in the country.

"It is important that business and the business of politics if you like does continue," he said, adding that an expert committee periodically reviews decisions about whether to permit travel to certain countries.