Scottish airline Flyglobespan has been placed in administration, it was reported tonight.
The airline operates flights from Edinburgh, Glasgow and Aberdeen, as well as transatlantic flights from other UK hubs including Manchester, Gatwick and Belfast.
A spokeswoman for administrators PricewaterhouseCoopers said a statement would be issued shortly.
No bookings were being taken on the airline’s reservation telephone line this evening.
Edinburgh-based Flyglobespan, a subsidiary of The Globespan Group, operated its first flight from the Scots capital to Nice in 2002.
The company is said to have been placed in administration after failed attempts to find a new investor.
Labour MP for Edinburgh North and Leith Mark Lazarowicz said: “This is a hugely worrying announcement for the 600 staff and all their families who will be desperately concerned.
“It will potentially be a massive problem to those who have booked their Christmas holidays with the airline, or who are overseas now.
“The administrators must ensure that people are protected and helped as much as possible.
“Coming just before Christmas, this is disastrous news.”
Low-cost airline Ryanair issued a “rescue fare” for passengers flying to and from Edinburgh and Glasgow Prestwick who are affected by the news.