Climate Change Minister Tim Groser has confirmed the New Zealand Government will ban some types of trading units from the Emissions Trading Scheme.
Questions have been raised about the environmental value of such units and Mr Groser said on Monday that the Government wants to maintain the integrity of the ETS.
The units are from some large-scale hydroelectricity projects and large schemes to destroy greenhouse gases.
Mr Groser said the ban is not expected to significantly reduce the supply of units in the period up to 2015, so is not expected to affect the carbon price.
The ban comes into effect on Tuesday.