The newest airline from Germany's Lufthansa Group, feeder airline City Airlines, is due to depart on its inaugural flight on Wednesday without collective agreements for airline staff.
The first departure scheduled is at 9:10 am (0710GMT) from Munich headed for the central English city of Birmingham.
On Tuesday, the pilots' union Vereinigung Cockpit (VC) and the flight attendants' union UFO confirmed that no agreement on the working conditions had been reached with the new airline.
This means that the transfer of staff from the existing subsidiary Lufthansa Cityline to the new company remains unclear.
The existing Cityline is expected to be wound down and replaced by the new City Airlines. Lufthansa chief executive Carsten Spohr had repeatedly pointed to restrictions on Cityline in the existing collective bargaining agreement as a key reason for the move.
The new City Airlines has offered voluntary transferees a bonus equivalent to one year's salary to make the jump.
However, the cabin crew union UFO has advised its members not to accept the offer, as many of the conditions unilaterally set by the airline on things like pay and working hours lag behind those under the collective bargaining deal at Cityline.
The Lufthansa Group intends to equip the new company for short and medium-haul routes with five aircraft before the end of this year.
In addition to Munich, the Lufthansa Group says that Frankfurt will follow next year as a second base and the City Airlines fleet is planned to grow by at least eight more jets.
A further 40 aircraft have been ordered for delivery after 2026.
The new City Airlines is fully integrated into Lufthansa's systems, and can only be booked through Lufthansa, similar to the arrangement with predecessor Cityline.
The pilots' union VC has described the launch of the new airline as unnecessary and superfluous but has indicated its willingness to negotiate over the Cityline deal.
