RNZ has approached the Act Party for comment.
Upton said in his letter the claims were incorrect and misleading because his report on the oil and gas exploration ban concluded “there is no firm basis for claiming that it will increase global emissions”.
“I most definitely did not say that the ban would increase global emissions,” the letter said.
The commissioner’s report did express concerns that the impacts of the ban were not fully analysed.
Overturning the ban was a policy of both Act and National, and the new Government has been criticised for it by green groups at the Cop28 climate summit in Dubai this week.
Upton’s letter ends with a suggestion that, after criticising the Labour-led Government for not making a careful analysis of the costs and benefits of the ban, “It would create an excellent precedent if your decision to lift the ban followed a thorough analysis of the costs and benefits of such a step.”
“Five years have passed since the imposition of the ban and much has changed since then.”