There's a lot on the line as the Trump administration considers expanding its laptop ban to include flights from Europe.
New security measures could result in major logistical disruptions at airports, and airlines might face reduced demand for lucrative tickets. Passengers could be hit by delayed flights and higher costs.
"We think that it could impose an additional cost of more than $1 billion on passengers," Alexandre de Juniac, head of the International Air Transport Association, said in a televised interview. "The Atlantic [route] is a big source of revenues and profits both for U.S. and European carriers. The impact could be significant."
The annual $1.1 billion cost estimate from IATA includes the loss of productive time in the sky for business travelers and longer travel times.
European officials met their American counterparts in Brussels on Wednesday to discuss aviation security, days after a potential expansion of the ban was first reported.
In a joint statement after the meeting, the U.S. Department for Homeland Security and the European Commission said they had discussed how to confront "the serious evolving threats to aviation security." They agreed to meet again in Washington next week.
The U.S. introduced rules in March that require any electronic device larger than a smartphone to be carried in checked baggage on flights from 10 airports in the Middle East and Africa. (It cited intelligence suggesting terrorists could hide explosives in bigger devices.)
That means no laptops in the cabin -- a major sticking point for business travelers.
Including Europe under the rules would be a dramatic expansion of the ban, and the aviation industry is concerned that additional resources would be needed to comply. Concerns have also been raised over the potential fire risk from storing large stocks of electronics in checked luggage.
On Tuesday, a US. official told CNN that various countries were "in a tizzy" over the issue.
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Here's why they're worried: The route between Europe and the U.S. is the busiest international corridor in the world. More than 350 flights depart Europe for the U.S. each day, according to IATA.
If business travelers ditch flying in favor of Skype or conference calls, airlines could be forced to operate fewer flights.
Emirates -- which was directly impacted by the original electronics ban -- said last month it was cutting back on flights to the U.S. because of weak demand.
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Expanding the ban to Europe would disproportionately affect U.S. airlines.
Delta Air Lines (DAL), United Airlines (UAL) and American Airlines (AAL) have the most to lose. British Airways would also suffer.
Combined, the four airlines account for nearly 60% of all nonstop flights from Europe to the U.S.
The broader U.S. tourism industry is also at risk.
The U.S. welcomes more than 14.5 million travelers from Europe each year -- that's 40% of all overseas visitors to America, according to research firm Euromonitor.
Most travelers from Europe are known to spend between $3,000 to $4,000 each time they visit the U.S., according to the U.S. Travel Association.
Visitors from Britain, Germany and France spend $31 billion each year on tourism and airfares to the U.S., according to the U.S. Travel Association. That's 15% of all overseas tourism spending in the U.S.
-- Rene Marsh contributed reporting.