Take-off and landing are the two prohibitive factors when it comes to adding a Dunedin leg to international flights servicing Queenstown.
Both Air New Zealand and Jetstar say it would not be commercially viable to add a stop at Dunedin International Airport.
The idea was raised following recent news Virgin had terminated Dunedin's only flights to Sydney and Melbourne.
That left a Dunedin to Brisbane flight as Dunedin's only international flight.
An Air New Zealand spokeswoman said while the airline constantly assessed the viability of new services, it had no plans to operate transtasman services to and from Dunedin via Queenstown.
''Adding an additional stop increases flight costs considerably, with additional handling and landing costs incurred.
''The extra fuel burn is also disproportionate to the additional distance flown, with take-off burning the most fuel over the course of a flight.''
Jetstar responded in a similar way.
A spokesman said low-cost carriers like Jetstar kept fares low by flying direct routes using jet aircraft, which was also the preferred option for most travellers.
The very short flying distance between Dunedin and Queenstown would not be commercially viable with a jet aircraft.
He said costs for everything from landing charges to baggage handling costs meant such a stop was not viable, on top of the high fuel costs of the short trip.
