Solid Energy has signed a deal to share transport and facilities with an Australian company mining coal on the West Coast.
The state-owned coal miner says the agreement with Bathurst Resources will allow the companies to develop export coal resources on the Denniston Plateau near Westport.
The companies have neighbouring resources and Solid Energy will transport 25% of Bathurst's coal by rail to Lyttelton Port.
Bathurst will locate some of its facilities inside areas covered by Solid Energy's coal mining licence.
Solid Energy will have access to Bathurst's infrastructure to reduce duplication of coal processing and transportation.