All travelers to the United Kingdom must have a negative COVID-19 test no more than 48 hours before departure starting Dec. 7, a move spurred by concern over the omicron variant, British Health Secretary Sajid Javid announced on Saturday, The Guardian reported.

England has also added Nigeria to its "red list" of blocked jurisdictions, which currently constitutes several countries in southern Africa with confirmed outbreaks.

Karen Dee, the chief executive of the Airport Operators Association, told the Associated Press that the new travel policy would act as a "major deterrent" to travel.

"This is a devastating blow for aviation and tourism," she said. "Pre-departure tests act as a major deterrent to travel, and most of the limited remaining demand following the reintroduction of self-isolation will now fall away, just as airports were hoping for a small uplift over the Christmas holiday.

"We don’t have the clinical evidence," Tim Alderslade, the CEO of Airlines UK, said about the omicron variant. "The red list extension made complete sense – that’s what it’s there for – but we know from experience that blanket restrictions do not stop the importation of variants."

British Transport Secretary Grant Shapps, who promised a day prior that authorities would not require a COVID-19 test before departure, said he understood the decision would be difficult for the travel industry.

"As the scientists work to understand new Omicron variant, we need to apply additional caution until picture is clearer," Shapps posted on Twitter. "We appreciate this will be difficult for the travel sector as we prioritise public health & protect the progress of our world-leading vax & booster programme."

The UK Health Security Agency said that the total number of confirmed omicron cases in the country was 160 on Saturday, up 26 from Friday.

• UK Set to Expand COVID Vaccine Boosters amid Omicron Fears
• EasyJet: Omicron Variant Already Affecting Flight Bookings