Shell Oil is warning that simply offering more blocks of land and seas for oil exploration does not necessarily mean it will happen.
The Government on Wednesday announced eight new areas for oil exploration, some of them extensions of existing zones and some of them new.
But last year's auction of oil exploration zones was undersubscribed, and this year's programme is still going on.
Shell New Zealand chairman Rob Jager welcomed the offer of more areas for exploration but said the issue extended beyond this.
"Investment decisions are not based on singular issues. They are a culmination of a whole range of things and we've got to be very careful that if we change part of that equation that we understand what the consequences may be," Mr Jager said.
Factors taken into consideration included the domestic gas market, the cost of doing business in New Zealand, being able to attract and retain staff, and the regulatory process.
"The whole range of things comes into that decision process. You've got to make sure you get the equation right in totality, not just the individual parts," he said.
The total area to be auctioned next year will be twice as big as the area under auction this year. The results of this year's auction will be known within a few weeks.