The Commerce Commission admits it will be under the pump getting a fuel market study done in 12 months.
The government announced yesterday an investigation into the petrol industry was officially underway - two months after Prime Minister Jacinda Ardern said consumers were being "fleeced" at the pump.
Fuel is the first target with the prime minister heavily critical of the varying prices at the pump across the country and the lack of information to back up why the gulf can be so huge from one city to the next.
She wants more transparency as soon as possible.
"My expectation would have been that we would have been able to do this more quickly, I have to take heed of the advice that we received from the Commerce Commission on that. They want to do it properly and I have to let them do their job,'' Ms Ardern said.
Commerce Commission chairperson Mark Berry said he expects the study to be completed in the 12-month timeframe but said it will be tight.
More details about the investigation will be released on Thursday.
The petrol companies said the study will give confidence to New Zealanders that they are not being ripped off.
Gull general manager Dave Bodger is all for the Commerce Commission having new powers to investigate but wants them to have the time they need to do it properly.
"I guess there is some concern there, I mean I don't know what they need to go through. Our businesses are getting the best value on fuel they can but if you're going to have an inquiry it needs to be worthwhile and I think the Commerce Commission doing it is important,'' he said.
National's commerce spokesperson Brett Hudson said if the government is serious about addressing the problem it could give immediate relief to consumers by axing fuel taxes.
"If they are concerned and then they can take action and axe the taxes that they put in place over the last 12 months. That would give Kiwis immediate relief in their back pocket, particularly heading into the Christmas period.''
It's Minister of Commerce Kris Faafoi's job to nominate industries that will come under scrutiny and he said he isn't short on suggestions for future studies from his Cabinet colleagues.
The Commerce Commission has been given a budget of $1.5 million per year for market studies - Mr Faafoi said he expects the petrol probe will use most of that.
A final report on the industry will be published by 5 December next year.