A new report suggests the shipping sector should be left to grow on its own, rather than being driven by the Government.
The report was commissioned by the Ministry of Transport, and prepared by the New Zealand Institute of Economic Research.
It examined the economic implications of possible options for freight services in the future - including having all imports and exports going via Australia, and New Zealand having two ports for very large container ships.
The report concluded all options were less beneficial than letting the sector evolve by itself, especially as competition intensifies as the global economy recovers.
The New Zealand manager of global freight firm Maersk, Julian Bevis, says port productivity needs to be addressed.
Mr Bevis says that the Government has an important role in facilitating discussions but that shipping lines prefer a market-driven rather than regulated sector.