By Sharon Marris, news reporter
Thomas Cook has ceased trading, the Civil Aviation Authority says as it launches a programme to bring stranded customers home.
The news comes after the company failed to secure the extra £200m needed to keep it afloat after a day of crucial talks with creditors.
Around one million customers who had travel booked in coming months have been told not to go to the airport, as all bookings, including flights and holidays, have been cancelled.
Peter Fankhauser, Thomas Cook's chief executive, said the tour operator's collapse was a "matter of profound regret", apologising to those affected.
He said executives had "worked extensively" in an effort to rescue the 178-year-old travel company, adding: "Although a deal had been largely agreed, an additional facility requested in the last few days of negotiations presented a challenge that ultimately proved insurmountable.
"It is a matter of profound regret to me and the rest of the board that we were not successful.
"I would like to apologise to our millions of customers, and thousands of employees, suppliers and partners who have supported us for many years."
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The collapse means that the CAA has launched the UK's biggest ever peacetime repatriation to bring Thomas Cook customers home.
The programme is expected to last until Sunday 6 October and will rescue almost twice the number brought home after Monarch Airlines failed in 2017.
Richard Moriarty, chief executive of the UK Civil Aviation Authority, said news of Thomas Cook's failure was "deeply saddening".
He added: "The government has asked us to support Thomas Cook customers on what is the UK's largest ever peacetime repatriation.
"We have launched, at very short notice, what is effectively one of the UK's largest airlines, involving a fleet of aircraft secured from around the world.
"The nature and scale of the operation means that unfortunately some disruption will be inevitable. We ask customers to bear with us as we work around the clock to bring them home."
The CAA's policy director Tim Johnson said 150,000 people would be repatriated on at least 40 planes over the next few weeks.
He told Sky News: "We expect to run around 1000 flights from the 55 destinations that Thomas Cook served.
"This is a huge effort, were working very closely with the government and Foreign Office in particular…But we're particularly appreciative and grateful for the support of a number of Thomas Cook employees who have clearly received this very sad news but they're going to be working with us over the coming few weeks to really help us manage this repatriation exercise."