Tui Group has said it will "absolutely not" turn away people who have not been vaccinated against Covid-19.
"This would be a mistake," said Tui Group chief executive Fritz Joussen.
"It’s not even 100% clear if a vaccinated person is infectious or not. Vaccination protects you, but on top of that you need testing.
"For us that is absolutely an important thing.
"The good thing is these tests are available. The disadvantage of PCR is it’s a longer wait for results.
"Most of our programme now has testing – we just test people before their flight."
Asked whether he though the cost of testing would deter travellers, Joussen said: "People got used to masks and they will get used to tests.
"We see an enormous acceptance. People value testing. They like to be tested and for others to be tested.
"They are not the problem for customer demand – currency is."