Beginning in November, all international travelers to the U.S. arriving by air will be required to be vaccinated, the White House announced Monday, in an easing of COVID-19 travel restrictions blocking entry to any residents from certain nations.

Under the new policy, foreign nationals must be vaccinated and show proof of vaccination before boarding a plane destined for the United States, said Jeff Zients, the White House COVID-19 coordinator. 

The vaccination requirement will come in addition to enhanced testing, contact tracing and continued masking requirements, he said. 

Specifically, foreign nationals will have to obtain a negative COVID-19 test within three days of boarding a plane, even with proof of vaccination. Fully vaccinated travelers will not be required to quarantine after arriving in the United States, he said.

Unvaccinated Americans returning from international travel, meanwhile, will need to show proof of a negative test within 24 hours of travel, he said. The Centers for Disease Control and Prevention currently recommends that unvaccinated Americans coming in from overseas be tested three to five days after returning and self-quarantine for seven days. Those who don’t get tested are asked to self-quarantine for 10 days after travel.

Monday’s announcement marks a reversal from what had been a ban on travel for non-U.S. citizens flying into the United States. Former President Donald Trump had restricted travel for foreign nationals coming from places including the United Kingdom, China, Brazil and Europe, and that restriction was unchanged when President Joe Biden took office.

But Zients said with nearly 6 billion shots administered globally, the U.S. is opting to move to a travel system that is “individual-based, rather than country-based.”

The vaccine requirement, he said, “is the best tool we have in our arsenal to keep people safe and prevent the spread of the virus.”

Sara Nelson, president of the Association of Flight Attendants-CWA, praised the new rules.

“International travel is essential to the stability of our jobs and the full recovery of the U.S. airline industry,” she said, “but recovery is only possible if we remain focused first on safety and health.”

U.S. Travel Association President and CEO Roger Dow, meanwhile, called the move “a major turning point in the management of the virus” that “will accelerate the recovery of the millions of travel-related jobs that have been lost due to international travel restrictions.”

The CDC will also take steps to enhance contact tracing, requiring airlines to collect phone numbers and email addresses from international travelers entering the United States. The CDC is also tasked with determining which vaccines will be considered acceptable under the new requirements. 

Zients said the CDC would issue an order in the “next few weeks” specifying the new contact tracing plans. Those new procedures, he said, “will also help strengthen the public health surveillance system against any future health threats.”

The new procedures will apply only to international travel, not domestic travel, Zients said.

But, he said, “we’re not taking any measures off the table.”