Australia and New Zealand represent natural partners in battling climate change, says Australian Prime Minister Kevin Rudd, who, along with Prime Minister Helen Clark, is addressing a climate change conference in Auckland.
Mr Rudd told the conference on Tuesday that the importance of being able to work closely with New Zealand at international climate change negotiations cannot be overestimated.
He praised Miss Clark's leadership in those negotiations, particularly when Australia had been absent from the table. "That's been really important in making sure that we are moving in the direction of a global consensus, despite all the obstacles."
Mr Rudd says both governments have been working closely on climate change mitigation and emissions trading.
Miss Clark says climate change will also be the focus of the Pacific Islands Forum in Niue, which both prime ministers are attending. "I think the change in position of the government in Australia on climate change is going to be very much welcomed there, and should lead to a very good and constructive discussion and outcome from the Pacific Islands Forum."
She says New Zealand will need to protect itself against the possibility of trade barriers being replaced by environmental barriers.
Miss Clark says New Zealand will have to make sure it deals effectively with greenhouse gas emissions from its biggest-emitting sector, agriculture, if it is to counter the imposition of environmental barriers against its exports
The two leaders have held an official meeting at Government House, and were due to leave for Niue on Tuesday afternoon.
Meanwhile, an Australian expert on climate change says the world's sea levels could rise by up to four metres by the end of the century.
Will Steffen, the head of the climate change unit at Australian National University and science adviser to the federal government, says he believes the scientific community is underestimating the speed at which the climate is changing.
Professor Steffen says polar ice sheets across the northern shelf are melting rapidly, and last year was a record year for ice loss.