The United States will soon ease COVID-19 restrictions for fully vaccinated travelers from overseas, a sweeping change that the travel industry and foreign governments have sought for months.

The new measures announced Monday will replace the patchwork policy that bans people who have been in specific regions in the previous two weeks, regardless of vaccination status.

The change could help make up for slumping demand in the domestic airline market, as carriers have struggled with coronavirus-related losses and high rates of delays and cancellations.

Flight bookings declined sharply in August, with those numbers extending into September, due to the spread of the delta variant. Carriers have since lowered their expectations for the rest of the year after signs in early summer that a comeback was in the making.

The effective date for the new travel policy isn’t clear, but the White House said it would happen in “early November” to give all sectors time to prepare.

“International travel is critical to connecting families and friends, to fueling small and large businesses, and promoting the open exchange of ideas and culture,” White House coronavirus response coordinator Jeff Zients told reporters Monday.

But even as the administration was announcing plans to loosen international travel requirements, the U.S. on Monday extended its restrictions, known as Title 19, for nonessential travel across land borders with Mexico and Canada through Oct. 21.

Once implemented, the new rules for international air travel will open the U.S. to millions of visitors, provided they can show proof of vaccination. Passengers will also need to present a negative coronavirus test taken 72 hours or less before departure.

There will be no quarantine requirement upon arrival, but unvaccinated Americans will need to provide a negative test within one day of departure and test again when they arrive. Travelers will also need to provide a phone number and email address for a new, “enhanced” contact tracing program.

Other key details, however, have yet to be worked out. It remains unclear which vaccines the U.S. will recognize, what the definition of fully vaccinated will be and whether there will be any exemptions allowed.

Zients said the Centers for Disease Control and Prevention will make those decisions.

Still, the announcement sparked optimism in the travel industry, which had been lobbying forcefully for the administration to lift restrictions.

The S&P 500 index of airlines rose slightly following the announcement.

“U.S. airlines have been strong advocates for a stringent, consistent policy and are eager to safely reunite the countless families, friends and colleagues who have not seen each other in nearly two years, if not longer. Today’s announcement marks a positive step in our nation’s recovery,” said Nicholas Calio, CEO of Airlines for America, which advocates for major U.S. airlines.

Sean Doyle, CEO and chairman of British Airways, called the change “historic” and said it should provide a “huge boost” to Great Britain.

“Our customers should now feel that the world is re-opening to them,” Doyle said.

His comments were echoed by Virgin Atlantic CEO Shai Weiss, who called the policy “a major milestone to the reopening of travel at scale across the Atlantic.”

“After 18 months of uncertainty, we cannot wait to welcome our customers back onboard, flying them safely to their favourite US destination,” Weiss said in a statement.

The heads of major U.S. airlines also welcomed the administration’s approach to lifting travel restrictions on Monday.

“With the shared goals of health and safety always at the forefront, we’re looking forward to welcoming more customers back to easy, seamless international trips for business, for leisure, and to reconnect with family and friends,” said American Airlines CEO Doug Parker, calling the new requirements a “science-based approach.”

While other countries have opened up their borders to fully vaccinated Americans, the U.S. has not reciprocated.

Former President Trump instituted a travel ban on China in early 2020, which was eventually expanded to include Iran, the United Kingdom, South Africa and the 26 countries in the European Schengen region.

Trump moved to lift restrictions on Europe and Brazil in the waning days of his administration, but President Biden kept them in place once he took office. Biden also added restrictions on India amid a surge of COVID-19 infections there.

Biden administration officials in June formed working groups with Canada, Mexico, the European Union and the United Kingdom to weigh when to lift international travel restrictions, and in mid-July it seemed the administration was close to announcing a change. But as the delta variant spread and infections rose, the administration said the closures would remain in place.

Monday’s announcement comes on the heels of increasing diplomatic tensions with France over a nuclear submarine deal with Australia and ahead of the annual United Nations General Assembly meeting in New York this week. European countries have been some of the most outspoken in their criticisms of the existing COVID-19 travel restrictions for the U.S.

A senior State Department official on Monday denied the policy change was aimed at patching relations with France and other European allies.

“This is really driven by the science of COVID, and as more people are being vaccinated around the world, we of course want people to be able to travel more freely,” said Erica Barks-Ruggles, an official in the Bureau of International Organization Affairs. “We’re really always being driven by the science.”

But the vaccination policy for international travel also puts further pressure on the administration to enact a similar requirement for domestic flights. Administration officials have been reluctant to take such a step, which would likely induce fierce pushback from Republicans and the travel industry.

When asked on Monday if there would be any change to domestic flights, Zients noted the fines for people who don’t wear masks when flying have been doubled. He also pointed to newly announced vaccine and testing requirements for workplaces.

There’s no effective date yet for the policy, which would require all companies with at least 100 employers to require either vaccination or weekly testing.

Morgan Chalfant contributed.