MPs on a special select committee tasked with reviewing the Emissions Trading Scheme are at odds over one of its terms of reference.
Under National's post-election deal with ACT, the committee is to take another look at the scheme, which National says was rushed through by the previous Labour-led government.
Parliament has agreed on the terms of reference for the committee.
One of the terms says the committee will look at the projections on which international climate change agreements are based; and consider the uncertainties and risks surrounding those projections.
National and United Future leader Peter Dunne, who is chairing the committee, insist that does not mean undertaking an investigation of climate change science.
But the Greens and Labour disagree.
Green Party co-leader Jeanette Fitzsimons says the whole question of whether climate change is real or not is on the table - and that will make New Zealand the laughing stock of the international science community.