The Agriculture Minister has told farmers that provisions giving agriculture time to adapt to an emissions trading scheme are more important than when the sector may be required to join.
Prime Minister John Key has said that an emissions trading scheme will need to include agriculture, but has also said the New Zealand scheme should be aligned to Australia, which not proposing to bring in agriculture until 2015 at the earliest
Under the current scheme, which is being reviewed by a select committee, agriculture would sign up in 2013.
The minister, David Carter told the Federated Farmers national conference that under the current scheme farmers would be gifted an allocation of 90% of 1995 agricultural emissions.
Those allocations would, under the current scheme, be removed at rate of 8% a year, which would have an "absolutely devastating effect" on the profitability of businesses, he said.
"I don't think at this stage we can pre-empt what might come from the select committee, and what ultimately Government might do.
"But rest assured the Prime Minister has given an absolute guarantee that it won't remove that level of initial gifting of allocation - grandparenting - at a rate that ruins the economics of farming."
Meanwhile, a series of meetings organised by the Government begins on Monday, aimed at consulting the public on setting target to reduce the country's emissions by 2020.
The Government intends to table the target at the next round of international Climate Change negotiations in Germany in August.