An anonymous consortium of rail users is trying to reopen the Gisborne to Napier railway line.
KiwiRail announced last year that it would mothball the line, saying it was too expensive to repair storm-damaged tracks and the service was losing money anyway.
The region's mayors and industries said the rail link was vital to the local economy.
Hawke's Bay Regional Council chairperson Alan Dick told Radio New Zealand's Checkpoint programme on Thursday a business case is being put together and it should be clear in six weeks if it is viable.
He said the consortium would establish a company to lease and repair the line.
Mr Dick said he won't name the group, but it involves a major transport operator and people who use rail networks in New Zealand and in Australia.