U.K. Travelers Must Test Negative for COVID-19 to Enter U.S. amid Concern About New Strain

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As concern over a new strain of the COVID-19 in the United Kingdom rises, new travel restrictions have been put in place for those crossing the pond into the United States.

All travelers must show proof of a negative test result within three days of flying into the U.S. from the U.K., the Centers for Disease Control and Prevention announced Thursday. Americans are advised to avoid traveling to the European country.

Back in March, President Donald Trump signed a mandate that restricted the entry of foreign citizens who had been to the U.K. within 14 days. After the new strain of COVID-19 began to spread more rapidly in the country, the European Union placed a travel ban on the U.K.

Recently, U.K. Prime Minister Boris Johnson announced that London and other parts of Southeast England would move to the highest level of restrictions over the weekend due to the new strain, which health officials say is spreading 70 percent faster than other variants of the virus.

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The variant, which Public Health England (PHE) has labeled "VUI – 202012/01" and was first identified in September, has been identified in COVID-19 cases in Australia, Denmark and the Netherlands.

"This additional testing requirement will fortify our protection of the American public to improve their health and safety and ensure responsible international travel," a statement from the CDC said of Thursday's new restrictions, NPR reported.

The new restrictions will take effect on December 28, and will require travelers to get a viral test within 72 hours of their flight and show their results to their airline. The CDC says not to travel while awaiting test results.

RELATED: Day Before Christmas Eve Saw Largest Number of Airplane Travelers in Single Day Since March

Despite continuing spikes across the U.S., Americans are still traveling despite the CDC's urgings against it. The day before Christmas Eve saw the most airport travelers in a single day since March. More than 1.1 million people were screened at airports on Wednesday, the Transportation Security Administration said.

The CDC previously released guidelines for holiday celebration this year that included urging people to stay "at home with the people who live with you."

In the U.S., there have been more than 18.7 million cases of COVID-19, and at least 329,237 people have died related to the contagious respiratory virus. Worldwide, there have been more than 79.3 million cases and more than 1.7 deaths from the virus.

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