Opposition parties say New Zealand is looking increasingly isolated at the United Nations climate change talks in Copenhagen.
For the past week, delegates from 192 nations have been meeting in the Danish capital to decide the future shape of a global climate change deal after the first phase of the Kyoto Protocol expires in 2012.
Ministers take over the process this week and the conference ends with a meeting of world leaders on Friday.
Greenpeace claims New Zealand negotiators are slowing down progress towards a deal.
Spokesperson Geoff Keey says New Zealand only notified its emissions reduction target in August - missing by months the UN deadline.
He also says New Zealand is still saying it is not ready to negotiate a firm reductions target.
"New Zealand has been saying in some of the closed meetings that we're not ready to negotiate on targets, we're only ready to have discussions.
"So New Zealand is actually helping slow things down, and holding up the works."
NZ must lift game - Opposition
Opposition parties say New Zealand will have to lift its game in Copenhagen if it wants to salvage any credibility.
Green Party MP Jeanette Fitzsimons, who is in Copenhagen, says New Zealand's opposition to restrictions on carbon trading may see it left out in the cold.
The UN has released official draft agreements that restrict the buying of carbon credits overseas to help countries meet emissions reduction targets.
New Zealand opposes the proposed restrictions.
"The New Zealand Government's position has been: We are going to do most of this by buying cheap credits from overseas, and therefore the more cheap credits there are, the better, " Ms Fitzsimons says.
"That's not going to be acceptable under this draft."
New Zealand's emissions reduction target of 10% to 20% by 2020 compared with 1990 levels falls short of suggested levels in the draft agreements.
Labour Party climate spokesman Charles Chauvel says New Zealand needs to work harder to reduce emissions domestically or it won't have any goodwill from other countries.
"We need that goodwill if we're going to be asking for the sort of concessions that we deem in our national interest - different rules on land use change (and) forestry planting.
"We can't go to the international community and ask for those concessions while stubbornly maintaining that we're not going to agree to decent targets."
Official draft agreements released by the UN during the weekend indicate modest progress, but major players including the United States and Australia are not happy with the proposals.
One draft suggests emissions reduction targets for developed countries to be set at a minimum of 25% by 2020 measured against 1990 levels.
However, it suggests developing countries try to slow their growth in emissions rather than reduce them.
The United States and Australia warn the draft is too soft on developing countries. The US says it will not be party to a deal without major industrialised nations such as China taking on tougher targets.
The exact target for limiting temperature rise remains unclear amid disputes between various blocs.
Small island states want temperature rises held to less than 1.5 degrees celsius, but other nations - including the US - want the limit to be 2 degrees celsius.
NZ in good position - PM
Climate Change Issues Minister Nick Smith and his associate minister Tim Groser are in the Danish capital, with Prime Minister John Key to join them later this week.
Mr Key believes New Zealand is in a good position going into the final week of negotiations. He acknowledges the country is a small player, but believes it must play its part.
"While we are a small country and on a relative basis a very small emitter, we play an important part in global solidarity to delivering a solution to climate change.
"But it'll be the actions and the commitments of those big nations of India, China, Brazil and the United States that will really determine whether we're going to get a successful outcome from Copenhagen."
Mr Key says he's happy with the make up of the New Zealand delegation despite criticism that business and agriculture groups are not included in the official party.
There are 23 people in the group, including government officials from the Foreign Affairs, Environment and Agriculture ministries.
The only non-government officials are two iwi representatives and two representatives from Tokelau.
Mr Key says it was made clear to business and agriculture groups that the delegation would be small, and they should seek their own accreditation, which he says many have done.