President Donald Trump’s 30-day ban on Europeans traveling to the U.S. delivered a hammer blow to airlines that are already facing US$113 billion in lost revenue worldwide this year because of the new coronavirus.

Foreign nationals who have spent two weeks in Europe, excluding the U.K., won’t be permitted to enter the U.S. after Friday, Trump said from the White House. Minutes after his late Wednesday announcement, his administration told American citizens to reconsider all foreign travel.

Flight restrictions are cascading around the globe as the pandemic threatens to spread to more countries. Trump’s controls will almost certainly mean more flights scrapped at European carriers and U.S. peers. Struggling companies like trans-Atlantic discounter Norwegian Air Shuttle ASA -- down 80 per cent this year -- may be pushed closer to the brink. The discounter parked 40 per cent of its long-distance fleet through May, and laid off 50 per cent of its staff.

Aviation stocks plummeted worldwide Thursday as broader markets moved into bear territory. A Standard & Poor’s index of nine U.S. airlines tumbled 20 per cent at the close in New York, the biggest drop since right after the Sept. 11, 2001, terrorist attacks. United Airlines Holdings Inc. paced declines among the country’s big carriers, falling 25 per cent to US$37.08, the lowest price since December 2013.

“However bad you thought it was, it’s worse,” said Cowen analyst Helane Becker. “We continue to believe near-term U.S. bankruptcies are unlikely, but our conviction is diminishing. Airlines are in cash-preservation mode.”

Boeing Co. -- already reeling from the worldwide grounding of its 737 Max, which hits the one-year mark Friday -- tumbled 18 per cent to US$154.84. That’s the lowest for the U.S. planemaker since late 2016. Airbus SE slid 17 per cent to 71.36 euros.

The industry as a whole has lost more than US$100 billion in market value so far this year, based on the Bloomberg World Airlines Index.

“Things are moving so fast,” said Brendan Sobie of the Sobie Aviation consultancy. “The crisis that the industry is facing right now is likely to be the worst in over 40 years.”

Trump’s ban will affect 11 per cent of all international flights and about 2 million seats each way over the next four weeks, data provider OAG Aviation Worldwide said. American Airlines Holdings Inc. and Delta Air Lines Inc. capped their economy fares between the U.S. and Europe.

Restrictions on European travel will hit some of the most popular long-distance routes. France, Germany and the Netherlands are home to three of the top 10 gateways across the Atlantic Ocean, according to the U.S. Transportation Department. The U.S. is the world’s largest air travel market, though China is catching up fast.

Airlines already faced unprecedented strains before Trump’s measures. With the public increasingly avoiding travel for fear of contracting the virus, the International Air Transport Association warned that passenger revenue might sink 19 per cent, or US$113 billion, this year. The total value of the market between the U.S. and the restricted European area was US$20.6 billion last year, according to the trade group.

National governments may need to provide credit to airlines to help them weather the blow, Alexandre de Juniac, chief executive officer of the group, said in an interview to Bloomberg TV.

“I don’t know of a government on this planet which has no interest in its airlines,” he said.

Sinking Valuations

Airlines skidded worldwide. Deutsche Lufthansa AG dropped 14 per cent. OAG said the German carrier accounts for 13 per cent of the flights between the U.S. and the affected area, the most among European airlines. The second, Air France-KLM, tumbled 13 per cent, the most since the global financial crisis in 2008.

British Airways owner IAG SA is among the least major carriers exposed, said Daniel Roeska, an analyst at Sanford C. Bernstein, because the ban excludes the U.K. and Ireland -- source of 85 per cent of IAG’s trans-Atlantic flights.

The declines followed slumps in Asia, with Singapore Airlines Ltd. plumbing its lowest close since September 2001.

Among other measures, the European Union will ease a requirement that carriers use at least 80 per cent of airport takeoff and landing slots or risk losing them, a rule that had led some carriers to fly empty planes. Lufthansa has also said it may seek state support via a German program under which the government offsets lost wages during work halts.

The U.S. restrictions caught many in the industry off-guard.

The travel sector had braced for additional flight restrictions, but the focus was on Germany and Italy, countries with serious coronavirus outbreaks, said Scott Solombrino, executive director of the Global Business Travel Association.

The trade group had just finished calculating that falling demand for travel to Europe could set the industry back by US$190 billion. “We’ll go back to the drawing board,” he said. “At the end of the day, the numbers are staggering.”

Trump’s controls on travelers from Europe don’t apply to legal permanent residents and immediate family members of U.S. citizens. Americans arriving from Europe will travel through specific airports where they can be screened for the virus.

The blow will be severe for U.S. carriers, said George Ferguson, an analyst for Bloomberg Intelligence.

“I think it hurts a lot. The big full-service guys, they make a lot of money across the Atlantic,” he said. “It’s absolutely the biggest international market and it’s their most lucrative international market.”

United Airlines will be particularly hurt because of its major operations in Frankfurt, Ferguson said. That comes on top of lost revenue from the ban on China flights and cutbacks to Asia, where United is the largest U.S. carrier. American Airlines will suffer the least thanks to extensive operations in London and a long-term alliance with British Airways, he said.

While strong balance sheets and other resources will allow most U.S. carriers to keep in business, problems will pile up if the outbreak doesn’t subside within the next month or two, Ferguson said. “It’s all a function of how long this virus lasts.”

The U.S. Travel Association said 850,000 visitors flew in to the country from Europe, excluding the U.K., last March, accounting for 29 per cent of total overseas arrivals. The visitors spent about US$3.4 billion in the U.S., it said.