Energy giant Shell will go ahead with drilling for gas in the Great South Basin.
A government-imposed deadline gave Shell until Friday to decide if it would start test drilling or forgo its claim.
The drilling programme is yet to be decided but ''will most likely target the early 2016 summer period'', the joint venture parties Shell NZ, OMV NZ and Mitsui E&P Australia said today.
"We are very grateful to the communities of Otago and Southland for the way in which they have engaged with us so far," Shell NZ chairman Rob Jager said.
''We will ensure that open and honest engagement with all interested parties continues as the project matures towards the drilling campaign."
Southland economic leaders said this week if drilling proceeded, Southland would not see any immediate financial impact but there could be future possibilities for the region.
The Green Party has called the venture "incredibly risky".
Energy spokesman Gareth Hughes said the venture should not be allowed to continue.
"We note that we saw Exxon Mobil vacate the permit in 2010 because of the hostile environment and the remote location.
"Those still exist so they're big factors for Shell and we think the risks outweigh the benefits," he said.
"So in a particularly hostile environment with significant ecosystems and conservation areas within it, we thinks it's an incredibly risky move that shouldn't be proceeding."
Hughes said the Government should be encouraging clean energy, "which would deliver more prosperity for New Zealanders but not imperil the environment".
He said there were also concerns over the permit border's close proximity to a marine mammal sanctuary off the coast of the Catlins.
"Obviously marine mammals would be seriously affected if we did see an oil spill occur.
Drilling would occur underneath water depths of more than 800 to 1200 metres.
"When you go drilling at depths such as this, the deeper you drill the greater the risk of a spill," Hughes said.
- Fairfax Media