Tui UK and Ireland has cancelled all beach holidays up to and including 10 July due to "ongoing restrictions".
All customers whose bookings are impacted by the changes will receive a refund credit and if their booking was for a package they will also get an up to 20% incentive, or they can request a cash refund via an online form on the Tui website.
All customers should receive their refund credit within four weeks before their original departure date, Tui said.
Customers due to travel before the end of August have the opportunity to amend their holiday for free, so they don’t have to pay until closer to their new departure date.
"We are constantly monitoring the situation and will start taking people on holiday again as soon as we are able to do so," the company said.