Climate Change Minister Tim Groser is under fire for not having any knowledge of an international index he said could have been produced by "green activists walking around in polar bear suits."
Mr Groser has just returned from talks in Peru where 190 countries agreed to a framework for pledges to cut greenhouse gases.
Asked about New Zealand's low ranking in the Climate Change Performance Index, Mr Groser told Morning Report's Guyon Espiner he had never heard of the index.
"I don't even know what the statistic is. I've got no idea whether these are green activists walking around in polar bear suits that put this together or governments, so I can't comment on the study," said Mr Groser.
"Never heard of it until you mentioned it," he said.
The index ranks New Zealand 42 out of 58 countries for its record on climate change.
Sustainability Council executive director Simon Terry said the minister should have known about the index, which had been operating for several years.
He was also concerned Mr Groser appeared to be conflating emission reduction targets with commitments.
"Tim Groser is claiming that New Zealand will meet its emission reduction target for the current period when that's not the case. Targets and commitments are quite different things and so while New Zealand can meet its committments it's not going to meet its emission reduction targets.
But Mr Groser said New Zealand was in very good shape internationally and the agreement reached at the conference in Peru would set the stage for more crucial talks in Paris next year.