A man dressed as Santa Claus gestures as people walk past, in London, Saturday, Dec. 4, 2021. Britain says it will offer all adults a booster dose of vaccine within two months to bolster the nation's immunity as the new omicron variant of the coronavirus spreads. New measures to combat variant came into force in England on Tuesday, with face coverings again compulsory in shops and on public transport. Credit: AP Photo/Alberto Pezzali

Britain's government tightened travel restrictions Saturday amid concerns about the spread of the omicron coronavirus variant, saying all travelers arriving in England will need to take a COVID-19 test before they board their flight.

Health Secretary Sajid Javid said the new rules will apply from 4 a.m. London time Tuesday.

"In light of the most recent data, we are taking further action to slow the incursion of the omicron variant," he said in a tweet.

Javid also added Nigeria to the U.K.'s "red list," which means that arrivals from there will be banned except for U.K. and Irish residents, and those travellers must isolate in designated quarantine facilities. He said there was a "significant number" of cases linked to travel with Nigeria, with 27 cases recorded in England.

Karen Dee, the chief executive of the Airport Operators Association, said the new measures will be a "major deterrent" to travel, just as airports and the travel industry were hoping for a small uplift over the .

"This is a devastating blow for aviation and tourism," she said.

Authorities recorded another 42,848 confirmed coronavirus cases in the U.K. as of Saturday, with 127 more deaths. With over 145,000 COVID-19 deaths in the pandemic, Britain has the second-highest virus toll in Europe after Russia.

  • Shoppers wear masks as they walk in Carnaby Street, in London, Saturday, Dec. 4, 2021. Britain says it will offer all adults a booster dose of vaccine within two months to bolster the nation's immunity as the new omicron variant of the coronavirus spreads. New measures to combat variant came into force in England on Tuesday, with face coverings again compulsory in shops and on public transport. Credit: AP Photo/Alberto Pezzali

  • People wear masks as they walk in Regent Street, in London, Saturday, Dec. 4, 2021. Britain says it will offer all adults a booster dose of vaccine within two months to bolster the nation's immunity as the new omicron variant of the coronavirus spreads. New measures to combat variant came into force in England on Tuesday, with face coverings again compulsory in shops and on public transport. Credit: AP Photo/Alberto Pezzali

  • A woman receives a dose of the Pfizer COVID-19 vaccine at Swaminarayan School vaccination centre, in London, Saturday, Dec. 4, 2021. Britain says it will offer all adults a booster dose of vaccine within two months to bolster the nation's immunity as the new omicron variant of the coronavirus spreads. New measures to combat variant came into force in England on Tuesday, with face coverings again compulsory in shops and on public transport. Credit: AP Photo/Alberto Pezzali

  • A person wears a face mask while crossing a road in Piccadilly Circus, in London, Saturday, Dec. 4, 2021. Britain says it will offer all adults a booster dose of vaccine within two months to bolster the nation's immunity as the new omicron variant of the coronavirus spreads. New measures to combat variant came into force in England on Tuesday, with face coverings again compulsory in shops and on public transport. Credit: AP Photo/Alberto Pezzali

  • A patient receives a dose of the Pfizer COVID-19 vaccine at Swaminarayan School vaccination centre, in London, Saturday, Dec. 4, 2021. Britain says it will offer all adults a booster dose of vaccine within two months to bolster the nation's immunity as the new omicron variant of the coronavirus spreads. New measures to combat variant came into force in England on Tuesday, with face coverings again compulsory in shops and on public transport. Credit: AP Photo/Alberto Pezzali

  • A patient receives the Pfizer COVID-19 vaccine at Swaminarayan School vaccination centre, in London, Saturday, Dec. 4, 2021. Britain says it will offer all adults a booster dose of vaccine within two months to bolster the nation's immunity as the new omicron variant of the coronavirus spreads. New measures to combat variant came into force in England on Tuesday, with face coverings again compulsory in shops and on public transport. Credit: AP Photo/Alberto Pezzali

  • A man receives a dose of the Pfizer COVID-19 vaccine at Swaminarayan School vaccination centre, in London, Saturday, Dec. 4, 2021. Britain says it will offer all adults a booster dose of vaccine within two months to bolster the nation's immunity as the new omicron variant of the coronavirus spreads. New measures to combat variant came into force in England on Tuesday, with face coverings again compulsory in shops and on public transport. Credit: AP Photo/Alberto Pezzali

  • A vial of the Pfizer COVID-19 vaccine ready to be used at Swaminarayan School vaccination centre, in London, Saturday, Dec. 4, 2021. Britain says it will offer all adults a booster dose of vaccine within two months to bolster the nation's immunity as the new omicron variant of the coronavirus spreads. New measures to combat variant came into force in England on Tuesday, with face coverings again compulsory in shops and on public transport. Credit: AP Photo/Alberto Pezzali

  • Vials of the Pfizer COVID-19 vaccine ready to be administered, at Swaminarayan School vaccination centre, in London, Saturday, Dec. 4, 2021. Britain says it will offer all adults a booster dose of vaccine within two months to bolster the nation's immunity as the new omicron variant of the coronavirus spreads. New measures to combat variant came into force in England on Tuesday, with face coverings again compulsory in shops and on public transport. Credit: AP Photo/Alberto Pezzali

  • A Pfizer COVID-19 vaccine is prepared at Swaminarayan School vaccination centre, in London, Saturday, Dec. 4, 2021. Britain says it will offer all adults a booster dose of vaccine within two months to bolster the nation's immunity as the new omicron variant of the coronavirus spreads. New measures to combat variant came into force in England on Tuesday, with face coverings again compulsory in shops and on public transport. Credit: AP Photo/Alberto Pezzali

  • Used syringes in a bin at Swaminarayan School vaccination centre, in London, Saturday, Dec. 4, 2021. Britain says it will offer all adults a booster dose of vaccine within two months to bolster the nation's immunity as the new omicron variant of the coronavirus spreads. New measures to combat variant came into force in England on Tuesday, with face coverings again compulsory in shops and on public transport. Credit: AP Photo/Alberto Pezzali

  • Empty vials of the Pfizer-BioNTech in a bin at Swaminarayan School vaccination centre, in London, Saturday, Dec. 4, 2021. Britain says it will offer all adults a booster dose of vaccine within two months to bolster the nation's immunity as the new omicron variant of the coronavirus spreads. New measures to combat variant came into force in England on Tuesday, with face coverings again compulsory in shops and on public transport. Credit: AP Photo/Alberto Pezzali

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