Tony Blair has defended an Asia-Pacific pact on climate change, saying it is not aimed at undermining the Kyoto Protocol on cutting gas emissions.
Mr Blair is touring Australia, New Zealand and Indonesia
During a visit to Australia, Mr Blair said the initiatives were "all tending in the same direction".
The Asia-Pacific partnership, of China, India, the US, Australia, Japan and South Korea, seeks technologies to cut emissions rather than setting targets.
The UK prime minister is on a tour of Australia, New Zealand and Indonesia.
In January, Australia hosted the first meeting of the Asia-Pacific Partnership on Clean Development and Climate.
Australia and the US have not signed up to the Kyoto Protocol, under which industrialised countries commit to cutting combined carbon emissions to 5% below 1990 levels by 2008-12.
They say Kyoto threatens economic growth and is worthless without commitments from major developing countries like China and India.
In Canberra on Tuesday, Mr Blair said: "I think the fact that you've got these initiatives at the moment, all tending in the same direction, is actually a positive sign, it's not a negative one.
"Britain is not going to be the country whose future determines the future of the planet and the climate.
"It's going to be about China, India and America, as well as of course the Europeans, and Japan and other countries like Australia.
"It is a completely unrealistic debate to say that you can have a climate-change agreement that doesn't involve China, and then America obviously, and then India, which is also a country of a billion people growing at a fast rate."
At a climate change conference in Montreal, Canada, in December, a broad group of countries including the US agreed to non-binding talks on long-term climate measures.
At a press conference alongside Australian Prime Minister John Howard, Mr Blair said: "We're going to have to see what is the framework that is going to incentivise business and industry and countries to develop the science and technology to allow us to grow in a clean way."
He added: "Will it be possible to get an agreement on such a framework? I don't think you can tell at the moment. Do we need one, in my view? Ultimately, yes, we are going to need a framework."
Mr Blair later travelled to Auckland, New Zealand. The last official visit from a British prime minister was made by John Major in 1995 for a Commonwealth heads of government meeting.
Mr Blair is due to hold discussions on Wednesday with Prime Minister Helen Clark, including looking at setting up annual talks on security issues.