Thousands of holidaymakers have been left stranded as tour operator Holidays 4 UK has gone into administration.
There are currently more than 12,000 people abroad who booked their package holidays with the Brighton-based travel company that also traded as Aegean Flights.
The Foreign Office has reassured stranded holidaymakers that the Civil Aviation Authority (CAA) will ensure they are able to fly home as planned.
The travel association ABTA estimates there are 12,800 people abroad in Turkey on package holidays booked with Holidays 4 UK and a further 20,000 bookings for holidays in the future - which have now all been cancelled.
Customers who booked package holidays with Holidays 4 UK will be able to claim a full refund for their holidays via the Air Travel Organisers' Licensing Scheme (ATOL) scheme administered by the CAA.
But passengers who just booked a flight will only be able to claim for this part of their holiday from the CAA and will have to contact the separate travel agent to ask about a refund for other bookings.
The advice for holidaymakers abroad is to stay in accommodation booked until they are due to fly home and if they do have to pay any extra for this (on top of the amount already paid when booking the package) a refund can be applied for from the CAA when they have returned home.
Ian Oakley-Smith, joint administrator and director at PricewaterhouseCoopers, says: "The company has suffered because of the difficulties faced by the travel industry during 2010 and 2011, as a result of the economic downturn."
A refund claim form can be found on the CAA website and customers who are currently abroad can call 0044 (0)161 444 5710 for more information.
Those in the UK should contact 0844 4933 037 or check the CAA website and twitter feed (@UK_CAA).
Has your holiday been affected by the collapse of Holidays 4 UK? Get in touch with us at firstname.lastname@example.org or in the comment box below.