Climate Change Minister Tim Groser is confident of progress towards the first globally binding treaty to reduce greenhouse gas emissions.
Tim Groser. Photo: NATIONAL PARTY
Mr Groser leaves on Saturday for the next week's United Nations climate change meeting in Warsaw of ministers and officials from 195 countries.
Negotiators at the annual meeting hope the new international treaty, a successor to the Kyoto Protocol, will be signed in 2015, to take effect from 2020.
Mr Groser says progress is being made, but it is imperative that the United States and China sign the treaty.
"It's a step on the way to the real thing that matters to us, which is to get a long-term agreement that, unlike Kyoto, gets all the main emitters in, because if we don't this time get the United States and China we're just wasting our time."