(CNSNews.com) - Australia should use its close ties with the United States to influence Washington to support the Kyoto Protocol, the politician leading the race to become the country's next prime minister said Monday.

The U.S. and Australia are the only industrialized nations that have refused to back the global pact, but Kevin Rudd has pledged to ratify it if his opposition Labor Party wins elections on Nov. 24.

Kyoto requires developed countries to reduce emissions of "greenhouse gases" -- carbon dioxide (CO2) and others often blamed for climate change -- by specified amounts by 2012.

More than 170 countries have ratified the protocol, and an international meeting in Bali, Indonesia, next month will consider a possible "Kyoto II" successor agreement for the period beyond 2012.

Australian Prime Minister John Howard, like President Bush, says he opposes Kyoto because of the cost to his country's workers and economy. They also argue it is unfair that Kyoto did not set emission reduction targets for large developing economies like China and India.

China is poised to overtake the U.S. as the world's largest CO2 emitter. According to the World Bank, China's CO2 emissions between 1990 and 2003 climbed by 42.1 percent. The U.S. figure for the same period was 16.8 percent.

Rudd, who has a comfortable lead in opinion polls to unseat Howard, said Monday that if Australia and the U.S. joined Kyoto, then China would have "no excuse other than to act."

"If we are to get countries like China and India to accept targets themselves, then developed countries must act first," Rudd told reporters at an environment policy-linked campaign event.

But his environmental spokesman, Peter Garrett, also told the Australian Financial Review that a Labor government would not consider it a "deal breaker" if developing nations did not immediately sign on to emission cut targets in a new Kyoto agreement.

China has given little ground on the matter.

At an Asia-Pacific summit last month, President Hu Jintao stressed the principle enshrined in Kyoto about nations' "common, but differentiated responsibilities" -- a formula that means industrialized countries should carry a greater emission-reduction burden than developing ones.

Howard said Monday that Labor's environmental pledges would harm the economy and reduce employment, not CO2 emissions. He told Australian radio: "We are willing to be part of an international agreement ... provided it also applies in an appropriate way to all of the world's major emitters."

"What is the point of having a situation where, perhaps by the year 2030, two-thirds of the emissions are coming from countries that are not part of the international agreement?" he asked.

The forthcoming election and Labor's strong showing has stoked green groups' campaigning, and climate change is dominating campaign platforms and headlines. Howard's stance took a blow with weekend reports that his environment minister, Malcolm Turnbull, had six weeks ago suggested to the cabinet that the government change direction and ratify Kyoto.

Howard's Liberal Party and Labor in recent days both seized on reports from abroad to bolster their positions on Kyoto.

Rudd on Friday pointed to a new U.N. Environment Program report that said the planet's natural and nature-based resources are at risk from rising temperatures, calling on world leaders to place the environment at "the core of decision-making."

"When the U.N. global environmental report talks about the absolute need for global cooperation to act effectively on the environment and climate change, a core part of that cooperation lies through the Kyoto framework," Rudd said.

Howard's stance also got a boost when two British scientists argued in the journal Nature that Kyoto was flawed from the start and had failed as an instrument for achieving emission reductions.

"Kyoto has failed in several ways, not just in its lack of success in slowing global warming, but also because it has stifled discussion of alternative policy approaches that could both combat climate change and adapt to its unavoidable consequences," said Gwyn Prins of the London School of Economics and Steve Rayner of Oxford University.

Former U.S. Vice President and global warming advocate Al Gore has called Australia and U.S. the "Bonnie and Clyde" of international climate change efforts. He told a business lunch in Sydney last month that if Australia dropped its anti-Kyoto stance, it would be impossible for the U.S. to withstand the pressure to join.

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