The country's carbon emission reduction promises are meaningless until the government fixes the Emissions Trading Scheme, the Labour Party says.
Climate Change Minister Paula Bennett signed the Paris Agreement at the United Nations in New York yesterday, and said she hoped New Zealand would ratify it within the next 12 months.
Labour's climate change spokesperson Megan Woods said the government needed to include agriculture in the Emissions Trading Scheme.
"The target New Zealand took is very dependent on carbon markets and us buying our way through to our [target] levels, but that's not going to be sufficient," she said.
"This government is going to have to confront the very real issue of agriculture and its place within the Emissions Trading Scheme."
"It literally is the cow in the room," she said.
The Emissions Trading Scheme is currently under review but agriculture has been left out of that review.
Dr Woods said New Zealand must also reduce emissions to meet its targets.
She said any agreement must not become a political football, and needed widespread support in Parliament.
Green Party co-leader James Shaw said his party would be pressuring the government to enforce its planned carbon emission reductions, by actually emitting less and not using "dodgy accounting tricks".
Mr Shaw said the country must set about reducing emissions, or the agreement would not be worth the paper it was written on.
"We need to raise our target, New Zealand has a target that's been described as inadequate," he said.
"It's the equivalent of a three to four degree (celsius) increase in global warming."
"We actually need to put in place some sort of programme to reduce our own emissions because so far our emissions have been rising relentlessly."
He said New Zealand could still lead the way on climate change action, and he would be holding the government to account on ratifying the agreement within 12 months.