Norwegian Air is set to cancel 4,000 flights and temporarily lay off about half of its staff because of the coronavirus outbreak.
The budget airline said the changes would apply until the end of May and numbers may increase.
Its boss said new restrictions on travel between the US and mainland Europe put “extra pressure on an already difficult situation”.
Analysts say airlines have been dealt another “body blow” by the travel ban.
Jacob Schram, chief executive of Norwegian, said this was “an unprecedented situation”.
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Many airlines are already under the cosh from the effects of coronavirus, and thousands of flights have been cancelled worldwide.
Korean Air has warned that the coronavirus impact could threaten its survival, and UK airline Flybe, which was already struggling, collapsed last week, saying the coronavirus outbreak was partly to blame.
‘Cash is king’
Airlines around the world are now assessing the impact of Mr Trump’s surprise 30-day ban and how it will affect revenues.
Analysts predict some airlines could fall into administration.
There are nearly 400 daily flights from Europe to the US, according to FlightAware, a flight-tracking service.
“In a crisis like this, cash is king,” said Michael Duff, managing director of The Airline Analyst.
He said transatlantic routes tended to be dominated by the major airlines, who should get through the crisis, assuming it lasts three to six months.
“Secondary players and regional and national European carriers are definitely facing severe survivability risk,” he added.
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Association of Flight Attendants-CWA President Sarah Nelson called the ban “irresponsible”.
“There is no explanation for how this will help fight the spread of the virus,” she said. “It makes little sense when the virus is already in the US.”
“Without any consultation with the industry, we don’t even know what this means,” she added.
The Association of Asia Pacific Airlines (AAPA) urged governments to refrain from introducing travel restrictions.
“Travel restrictions cause significant disruptions to supply chains, commerce, trade and most importantly to peoples’ livelihoods due to the severe economic impact,” said Andrew Herdman, AAPA director general.