The hurdles have included “chaotic border restrictions along with confusion about quarantines, varying passenger locator forms and test requirements,” Airlines For Europe (A4E) director Thomas Reynaert said in a press conference held by video.

To overcome the piecemeal measures, A4E urged a “common approach”, backing calls from the European Commission for a central colour-coded map of areas in the bloc where the virus risk, is high to enable restrictions by region rather than “blanket national restrictions”.

Passengers should have access to “quick and reliable Covid-19 tests” and quarantines should be downgraded to “an instrument of last resort”, the airline group said.

“Low-risk” travellers including pilots and cabin crew ought to be excluded from travel restrictions, the companies added.

The airlines' appeal to governments comes after August saw passenger traffic plateau at around 30 percent of its level a year ago, according to A4E's own figures.

“A unified European testing programme is urgently needed if we are to have any chance of restoring passenger confidence,” Reynaert said.

Greater EU-wide coordination should be made a “political priority”, Air France-KLM chief and A4E chairman Benjamin Smith said.

“Uncoordinated national measures over the last six months have had a devastating impact on freedom of movement.”