Monarch Airlines has ceased trading and its 300,000 future bookings for flights and holidays have been cancelled, according to the Civil Aviation Authority.
Around 110,000 of the company's customers are abroad and government officials have asked the CAA to step in, chartering more than 30 planes to bring them home.
Stephen Morton-Prior, managing director of Clearwater Events, said: "It's sad because Monarch specialises in customer service. Ryanair, whose focus isn't so much on customer service, are cancelling thousands of flights but will probably be fine, while Monarch who have been going for 50 years have to cease trading.
"Monarch inspired me to become a flight attendant when I was 21. Those fabulous uniforms and shiny DC-10’s made me want to jump into the clouds and fly for a living.
"It's a great brand and perhaps the MICE industry could have supported it more. If they'd hung on another month or two they'd have definitely picked up a lot of bookings from events professionals who are not confident booking with Ryanair. Their flights to Geneva, for example, would have been very popular."
No longer operating
A statement on the firm's website said: "As a result, we are sorry to inform you that, as of 2 October 2017, all future holidays and flights provided by these companies have been cancelled and are no longer operating.
"This is an unprecedented situation and because there are up to 110,000 passengers abroad, the UK Government has asked the CAA to coordinate flights back to the UK for all Monarch customers currently overseas. These new flights will be at no extra cost to you."
Monarch confirmed that the following companies have ceased trading and now entered administration:
- Monarch Airlines Ltd
- Monarch Holidays Ltd (ATOL Number 2275)
- First Aviation Ltd (ATOL Number 4888) previously trading as Monarch Airlines
- Avro Ltd (ATOL Number 1939)
- Somewhere2stay Ltd
The CAA said: "This is the biggest ever UK airline failure. The CAA and Government are working together to support Monarch customers."
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