Tour operators have been hit by soaring fuel costs
About 600 Northern Ireland holidaymakers are believed to be stranded abroad following the collapse of tour operator group XL.
Belfast International Airport said passengers booked on XL flights next week should not go to the airport.
The Civil Aviation Authority (CAA) will handle the repatriation of those stranded abroad.
Belfast man Jon O'Rourke was due to go to Rhodes, but said he would have to wait for a £600 refund.
"It's credit crunch time - so-called - and I don't have, my girlfriend doesn't have more money to fork out for another holiday while we are waiting on the refund of the cancelled one - it's just absolutely ridiculous," he said.
The firm also operated flights from Dublin to Spain and Greece.
Four flights were scheduled for Friday.
Andrew Muir from County Down said his parents were due to return from America with the operator.
They are on a Caribbean cruise and are to return from Florida in a few days.
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"They are on a cruise ship so nobody can contact them and are probably oblivious to what is happening," he said.
"That cruise ship docks in a few days and I found out about this last night."
A Belfast International spokeswoman said XL flew three times a week during the summer season - to Corfu on a Monday, Crete on a Tuesday and Rhodes on a Wednesday.
"While XL was a popular travel company with our customers the vast majority of holidaymakers in Northern Ireland continue to fly out of Belfast with Thomas Cook and TUI, over a quarter of a million this year alone," she said.
The Republic of Ireland's Commission for Aviation Regulation said people who have not started their holiday will be unable to travel and that it would make arrangements to repatriate those stranded abroad.
The tour group also operated from Dublin airport
However, it said those due to return on Friday should make their own way home and claim their costs from the commission.
The CAA said 85,000 people across the UK could be stranded abroad and 200,000 have made advance bookings with the company.
David Clover, a spokesman for the CAA, said it would be making arrangements to help customers of the four tour companies within the XL group and was working "very closely with the travel industry to organise repatriation flights".
XL Leisure Group
XL Airways UK
Freedom Flights (Aviation)
The Really Great Holiday Company
Travel City Flights
Kosmar Villa Holidays
The group is the latest travel business to face financial difficulties, as the industry struggles with high fuel costs and an economic downturn.
The XL group, which is based in Crawley, West Sussex, runs an airline and owns several travel companies, including Travel City Direct, Medlife Hotels Limited, The Really Great Holiday Company, Freedom Flights and Kosmar Holidays.
The group, which carried 2.3 million passengers last year, has 1,700 employees worldwide.
A statement on the XL group's website said: "The companies entered into administration having suffered as a result of volatile fuel prices, the economic downturn, and were unable to obtain further funding."
Package holidaymakers have financial protection under the Air Travel Organisers' Licensing (Atol) scheme.
But customers who booked directly through the XL website or call centres are not protected.
People who booked through a credit or debit card can contact their card issuer to see if they can refund their money.