Passengers on long-haul flights may need to prove they are Covid-safe before they are able to fly, an airline industry chief warned.
Lufthansa chief executive Carsten Spohr said he did not want to introduce the system, which would add another hurdle to travelling at a time when few people are flying, but he accepted it might be needed.
Since coronavirus spread around the globe, the airline, travel and tourism industries have been battered by the lockdowns and social distancing that are vital to trying to curb the disease.
Airlines and plane-makers have seen profits slump and tens of thousands of people have lost their jobs.
Mr Spohr said Covid tests and vaccinations could get people flying again and help travellers to feel safe.
"Personally, I assume that in the future every passenger on certain intercontinental routes will be either tested or vaccinated," Mr Spohr said.
Lufthansa will first increase the number of routes that have rapid Covid testing facilities.
"In the second phase, there will probably be an option between a test or proof of vaccination," he said.
He said Lufthansa did not want to make it compulsory for passengers to have either proof of vaccination or a Covid test confirming they are healthy. "As an airline, we neither can nor want to stipulate that," he said.
He added that a vaccine certificate would become superfluous once widespread immunity and vaccinations have been achieved.
Lufthansa needed a multi-billion-euro rescue package and its sales dropped by two-thirds in 2020.
The German airline announced another package of restructuring measures in July, including a 20 per cent cut in leadership positions and the reduction of 1,000 administrative jobs, as it battles with the fallout from the coronavirus pandemic.
The airline said it would also cut investment planned for new aircraft by half, with its financial plan allowing for up to 80 new aircraft for the group's fleet up to 2023.
Elsewhere, British Airways has axed services to more than 15 long-haul destinations, including Abu Dhabi, in 2021, as the carrier struggles to recoup losses sustained by the collapse in air travel caused by the pandemic.
Other Middle Eastern destinations affected by BA's pared back operations include Jeddah, Saudi Arabia, and Muscat, Oman.
"We are sorry that, like other airlines, due to the current coronavirus pandemic and global travel restrictions we are operating a reduced and dynamic schedule," BA said.
BA posted a £4 billion ($5.42bn) loss for the first half of this year and made about 10,000 staff redundant in the summer.
