The International Air Transport Association (IATA) expects its digital Covid Travel Pass will be ready for use “within weeks”.
The pass - which was originally unveiled in December - is designed to verify a passenger has had the Covid-19 tests or vaccines required to enter a country.
It also verifies they were administered by an approved authority.
The industry body sees the pass as essential for reopening air travel, as many countries still have strict restrictions or quarantines in place.
“The key issue is one of confidence,” Vinoop Goel, IATA regional director of airports and external relations, said.
“Passengers need to be confident that the testing they have taken is accurate and will allow them to enter the country.
“Then governments need to have the confidence that the tests that the passengers claim to have is one which is accurate and meets their own conditions.”
IATA said the Travel Pass – which it is preparing alongside Etihad and a number of other carriers - is designed in a modular way, so that it can work with other digital solutions that are being trialled around the world.
British Airways, for example, is working on a separate, but compatible, VeriFLY solution.
IATA said the Travel Pass will be available on iOS and Android platforms, and is expected to be free to passengers.
“We are building the IATA Travel Pass with one aim - to help reconnect our world safely.
“IATA has brought advancements in global standards like e-ticketing and mobile boarding passes to consumers in all parts of the world.
“This unique capability demonstrates that we can work with industry and governments to re-shape travel processes based on global standards,” said Nick Careen, IATA senior vice president, airport, passenger, cargo and security.