The deal reached at global climate change talks in Copenhagen has disappointed politicians and scientists worldwide, while reaction has been mixed in New Zealand.

Prime Minister John Key has described the deal as "short of the aspirations and expectations" people held, while the Green Party's former co-leader Jeanette Fitzsimons has labelled it a "tragedy for humanity."

Labour Party climate change spokesman Charles Chauvel, who also attended the conference, said the deal could be built on.

Prime Minister John Key’s speech to leaders at the Copenhagen summit last night reflected New Zealand’s focus on low-carbon development, innovation and influencing priorities for finance and investment.

Any global deal needed to be able to evolve and keep up with scientific knowledge, technological breakthroughs and economic and social development, he said.

It was sobering to have reached a point of the conference without having made progress on the major issues necessary for a legally binging agreement, he said.

Prime Minister John Key’s speech to leaders at the Copenhagen summit last night reflected New Zealand’s focus on low-carbon development, innovation and influencing the priorities for finance and investment.

Any global deal needed to be able to evolve and keep up with scientific knowledge, technological breakthroughs and economic and social development, he said.

It was sobering to have reached a point of the conference without having made progress on the major issues necessary for a legally binging agreement, he said.

Ministers from 20 countries have joined a Global Research Alliance on agriculture greenhouse gases that New Zealand has pledged $45 million towards over four years.

Prime Minister John Key proposed the alliance at the UN General Assembly in September and New Zealand ministers have “heavily” promoted it as an initiative to bring developed and developing countries together on the issue.

Associate Climate Change Minister Tim Groser and Agriculture Minister David Carter announced the alliance, formed in Copenhagen overnight.

Japan is the most sustainable country in the Asia Pacific within the G20 countries, global researcher IDC announced at the United Nations Climate Change Conference in Copenhagen on Friday.