Tui has cancelled the majority of its May and June departures to a handful of amber and red list countries.
All of Tui’s Mexico, Dominican Republic, Costa Rica, Turkey, Egypt, Cape Verde, Morocco, Tunisia and Bulgaria holidays are off until 28 June at the earliest.
Turkey and Cape Verde are currently on the UK government’s red list, while the remaining seven are on the amber list.
Tui said the decision came amid the "ongoing uncertainty" over travel this summer, and reiterated it would continue to operate to countries with open borders and where the Foreign Office allows travel.
Customers impacted by the latest round of cancellations will be able to request a full refund, or move their booking to a later date or different location and receive a booking incentive.
"We want to offer our customers flexibility and choice this summer, so where borders are open and FCDO advice allows travel, we will operate to those destinations as planned," said Tui, which is operating to several amber list destinations, including Crete (Heraklion), Kos, Rhodes, Corfu, St Lucia, Cuba (Varadero), Antigua, Barbados, Grenada.
It plans to offer Canary Islands holidays to Tenerife, Gran Canaria and Fuerteventura from 27 May and Crete (Chania), Zante, Malta and La Palma from 7 June.
"We are constantly reviewing our holiday programme and cancellations in line with the government updates every three weeks, with the next update due in early June," added Tui.
"If we need to cancel any future holidays because of updated government guidance, we will be in touch with you directly and will aim to give you at least seven days’ notice."
Like Tui, easyJet holidays is operating to select amber list destinations, while Jet2holidays is currently due to restart its holiday programme from 24 June.
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