The largest-ever climate talks has formally opened in Denmark aiming to agree the outlines of a global deal to hold off dangerous climate change.
About 15,000 participants from 192 nations gathered in Copenhagen on Monday seeking to agree cuts on greenhouse gas emissions and raise billions of dollars for the poor in aid and clean technology.
The United Nations-organised conference will try to work out a global deal to fight climate change after the first phase of the existing pact, the Kyoto Protocol, ends in 2012.
Campaigners say politicians have two weeks to save the Earth from catastrophic climate change in the talks, which end on 18 December with a summit of 105 world leaders, including United States President Barack Obama.
The New Zealand delegation is being led by Dr Nick Smith, the Minister for Climate Change Issues. Prime Minister John Key is to attend the leaders' summit.
The conference in the Danish capital will have to overcome deep distrust between rich and poor nations about sharing the cost of emissions cuts, Reuters reports.
The attendance of the leaders and pledges to curb emissions by all the top emitters - led by China, the US, Russia and India - have raised hopes for an accord after sluggish negotiations in the past two years.
"Copenhagen is already a turning point in the international response to climate change," Yvo de Boer, head of the UN Climate Change Secretariat, said.
Mr de Boer wants developed nations to agree to deep cuts in greenhouse emissions by 2020 and come up with new funds to help the poor cope. He is calling for developing nations to start slowing their rising emissions.
World leaders did not attend when environment ministers agreed the Kyoto Protocol in 1997.
This time, in a conference hall with wind turbines outside generating clean energy, Danish Prime Minister Lars Lokke Rasmussen and Rajendra Pachauri, head of the UN's panel of climate experts, will be speak at the opening session on Monday.
Plans by world leaders to attend have brightened hopes since Mr Rasmussen said last month that time had run out to agree a full legal treaty in 2009. The aim for Copenhagen is a politically binding deal and a new deadline in 2010 for legal details.
A worldwide survey, commissioned by the BBC World Service, suggests public concern over global warming is rising, with more than 60% supporting public expenditure being used to tackle the problem.
Some 56 newspapers from 45 countries including The Guardian, Le Monde, El Pais and the Toronto Star on Monday published a joint editorial urging world leaders to take decisive action.