New Zealand believes it has made a breakthrough in its plan to cut methane emissions from its livestock, part of a strategy to tackle greenhouse gasses, the farming nation's trade minister said on Wednesday.

"Our agricultural research organisation just last week was able to map the genome ... that causes methane in ruminant animals and we believe we can vaccinate against (that)," Phil Goff told a conference in Paris.

Scientists in New Zealand are working on other ways to reduce emissions from agriculture, such as changing the way fertilisers are used on pasture land, he said.

Goff was talking about New Zealand's approach to emissions trading systems, one of the main instruments being introduced by developed countries to counter global warming.

New Zealand plans to include methane and nitrous oxide as well as carbon dioxide in its emissions trading scheme which is due to be launched in July.