(Bloomberg) -- The U.K. will require all travelers to take a pre-flight Covid-19 test within 48 hours prior to their flight -- regardless of their vaccine status -- as the government seeks to stem the spread of the omicron variant, Health Secretary Sajid Javid told Sky News.

The measure will be temporary and be reviewed as the omicron outbreak develops, he said. More than 100 people in the U.K. have been identified with the new variant, which is rapidly spreading across the globe.

The new rules go into effect on Dec. 7. 

Travelers will be allowed to take either an instant test or a PCR test. After omicron was detected in the U.K. a week ago, the government added a required PCR test within two days of arrival, requiring travelers to self-isolate until they received a negative result. 

The move may put more pressure on airlines and other travel-related companies just before the peak Christmas season.  

Javid also announced that Nigeria would also be added to its red list of countries that require a 10-day hotel quarantine at the traveler’s expense. 

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