TUI has cancelled holidays to Malta and certain parts of Italy – Sardinia, Sicily and Calabria – or holidays in Almeria and Girona in Spain until October 31.
Holidays to Cancun, Mexico, Naples, Italy, and India were also cancelled until August 31.
The holiday firm is continuing to offer holidays to green and amber list destinations in the Balearics – Ibiza, Majorca and Menorca – and the Canaries – including Tenerife and Gran Canaria – and Malta with non-Tui flights.
The company has taken the decision to halt holidays to red list destinations or any countries where British travellers would be required to quarantine on arrival.
A spokesperson said: “If we need to cancel holidays because of updated government guidance, or after reviewing our holiday programme, we will contact customers and aim to give at least seven days advance notice.”
Full refunds will be offered to customers or they will be offered a booking incentive to change their holiday to a later date.