A single shot of either the AstraZeneca or Pfizer vaccines is more than 80% effective at preventing hospitalisation among the over 80s, the health secretary has said.
Speaking at a Downing Street news conference, Matt Hancock said: "This shows, in the real world, across the UK right now that the vaccine is helping both to protect the NHS and to save lives."
Three cases of the P.1 coronavirus variant have been confirmed in England and three in Scotland, Public Health England said.
Two of the cases in England come from a household in South Gloucestershire, where one person returned from Brazil in mid-February, before hotel quarantine measures were introduced.
The third case is unlinked and the whereabouts of the individual unknown, as they did not complete their test registration card.
The three Scottish cases were found in asymptomatic passengers who flew into Aberdeen on the BA1312 flight from London Heathrow on Friday.
They tested positive while self-isolating and contact tracing of other passengers on the flight is currently ongoing.
The Scottish government said there was "no reason to believe" the P.1 variant is in circulation in Scotland.