The U.S. has tightened pre-travel testing rules and extended mask mandates for travelers in response to the omicron variant.

The Biden Administration has unveiled a comprehensive strategy aimed at combating the omicron variant of the coronavirus, which includes significant changes for travelers.

The new measures, revealed by the White House on Thursday, involve strengthening pre-departure testing mandates for international travelers. Beginning Monday, Dec. 6, 2022, all individuals traveling to the U.S., regardless of vaccination status, must present a negative COVID-19 test conducted within one calendar day prior to their departure. This requirement applies to all international flights arriving in the U.S. after 12:01 a.m. Eastern Time on Dec. 6.

This mandate affects not only international visitors but also U.S. citizens and residents returning to the country. Previously, fully vaccinated individuals had a three-day testing window, which will now be reduced for all travelers starting Monday.

This action aims to curb the transmission of the omicron variant in the U.S. The World Health Organization (WHO) has already classified omicron as a 'variant of concern.' Last week, the Biden Administration also enacted a temporary travel ban from eight Southern African nations.

The federal mask requirement for airplanes, trains, and other public transport has been extended until March 18. Travelers are required to wear masks during international trips and in public transit hubs like airports and indoor bus stations. The Transportation Security Administration (TSA) will continue to enforce these mask rules, with fines starting at $500 and potentially escalating to $3,000 for repeat offenders.

On Thursday, President Biden is anticipated to outline the U.S. strategy for combating a potential COVID-19 resurgence this winter, including the continuation of the mask mandate. Part of the new COVID response plan involves increasing access to free at-home COVID tests for Americans via testing sites, community centers, and clinics in rural areas.

Two confirmed cases of the Omicron COVID variant have been identified in the U.S.—the first case in California and the latest involving a Minnesota man who had recently traveled to New York City.