Holidaymakers due to travel to Spain, Cyprus, Portugal and Morocco have been faced with further disruption, as TUI has cancelled more of its flights.
Flights were originally cancelled up to mid-August, but have since been extended due to recent spikes in coronavirus infections.
How long are flights cancelled for?
As both Spain and Portugal are still on the UK government’s travel ban list, due to the high number of coronavirus cases in those countries, TUI has extended the length of its cancellations.
Flights to both countries were initially cancelled until 17 August, but this has now been pushed back a further two weeks.
All flights and holidays to mainland Spain and Portugal are cancelled up to and including Friday 28 August, while the Balearic and Canary Islands are cancelled up to and including Sunday 23 August.
Depending on the travel advice, cancellations to these countries could be extended again.
Cyprus holidays are cancelled up to Sunday 23 August, while holidays to Morocco have been cancelled until Friday 11 September.
Any travellers who are entering Cyprus from the UK must have a negative coronavirus test, which should be taken no more than 72 hours before travelling.
Can I cancel my booking?
Customers who have booked holidays between 23 and 31 August which have not yet been cancelled are able to amend them free of charge, with a £500 incentive, or cancel for a full refund.
In a statement, TUI said, "All affected customers will be able to amend their holiday for free and receive a booking incentive or cancel and receive a full cash refund.
"We know this is very disappointing for those looking forward to their well-deserved break. The health and safety of our customers and colleagues is always our highest priority."
TUI is also offering to cover all medical expenses and repatriation costs for UK holidaymakers who test positive for coronavirus while abroad.
The tour operator will pay for any tests and health treatments, as well as any extended hotel stays enforced due to the virus. The announcement is part of the holiday company's Holiday Promise, which will only sell holidays without strict restrictions and changes for tourists.