Parliament's independent environment watchdog is recommending that the Emissions Trading Scheme be strengthened.
The scheme is being reviewed by a paenl looking at what changes, if any, should be made.
The ETS is part of the Government's attempts to meet New Zealand's international obligations around climate change.
Climate Change Minister Nick Smith has previously indicated that agriculture could be delayed from entering the scheme in 2015.
But in her submission to the ETS Review Panel, the Parliamentary Commissioner for the Environment says that would send a negative signal to the international community.
Jan Wright says such move would bring into question New Zealand's commitment to carbon reductions and would be likely to affect its clean, green image.