Anadarko, the troubled oil giant involved in the Gulf of Mexico disaster, must make a call by the end of August on whether to spend tens of millions of dollars off the Otago coast.
The explorer has a 25 per cent stake in the gushing Gulf field and its shareprice plunged by 19 per cent yesterday to US$34.83 ($51.50) - its lowest level in five years - on fears over its liability for the clean-up which could run into billions for the Texas-based company alone.
It holds a 50 per cent stake in the Carrack and Caravel prospects in the Canterbury Basin and must, with equity partner Origin Energy, decide by August 21 whether to go ahead with an exploration well.
The cost of a well could be more than $100 million.
It also has a 45 per cent stake in a longer-term deep water prospect off the Taranaki coast.
Anadarko has said US President Barack Obama's moratorium on deep water drilling off the United States means it will consider reallocating money to other projects around the world.
While Anadarko could not be reached for comment on its New Zealand plans yesterday, Origin Energy says that no decision had been made on its Canterbury Basin project.
"We're still in discussion about the programme and haven't reached a decision yet," said New Zealand general manager Chris Bush.
The Petroleum Exploration and Production Association says it is unclear how Anadarko's New Zealand plans could be affected.
Executive officer John Pfahlert said: "It may be the President's ban on drilling for six months means they've got a whole bunch of resources that have to go somewhere else.
