Europe's largest airline group Lufthansa said Tuesday it was retiring "ladies and gentlemen" as an on-board greeting in favour of gender-neutral alternatives.

A spokesman for the German company told AFP the move was intended to make all passengers on board feel welcome, including those who do not identify as male or female.

"Crews are being instructed to choose a greeting that includes all passengers," he said, adding that "dear guests" or a simple "good morning/good evening" would be used instead.

The new policy, which will be phased in gradually, applies to German flag carrier Lufthansa as well as the group's Swiss, Austrian, Brussels and Eurowings airlines.

The company said it was responding to a "discussion that is rightly being held in society" about non-binary gender identification and a desire "to value all guests on board".

Germany has joined the international debate about more inclusive language to take into account diverse gender identities and an increasingly multicultural society.

In recent days, major cities including Berlin, Munich and Hamburg said that their transport networks would stop using the word "Schwarzfahren" (black riding) to describe travel without a ticket in response to complaints the word had a racist taint.