The Energy Minister has also admitted no formal consultation with the Petroleum Exploration and Production Association of New Zealand (PEPANZ) took place.

"No formal consultation was undertaken with PEPANZ in relation to the decision to grant no further offshore oil and gas exploration permits. However, I have spoken publicly about the Government's direction to transition away from fossil fuels and my office has had open dialogue with PEPANZ before this announcement."

There's also been no estimates on whether global greenhouse gas emissions will fall as a result of the decision.

"No specific estimate has been provided to me. I have been advised by officials that the effect on global emissions depends on the response of New Zealand's large gas users."

Seymour says that's the most damning revelation.

"The worst part of this policy announcement is they haven't even figured out if it will achieve its intentions," he said.

"They don't know how much substitution of coal should occur, and if the net result is people moving to coal, net emissions will be even worse than they are now. I've seen some own goals in my time in politics. This Government is an expert."

Advice or estimates on increases or decreases to gas prices are also missing from the background work on the policy.

"No specific estimate has been provided to me on the price impact on gas of the decision to grant no further offshore oil and gas exploration permits. Officials have advised that gas prices have risen in the past when the supply of gas has been constrained," Dr Woods said.

Newshub.