Milne was invited to speak in Montreal at last week's United Nations Framework Convention on Climate Change meeting, in her role as vice-president of the World Conservation Union.
Milne said that while she was at the conference, she held "informal discussions" with some of the delegates from Australia's APPCDC partners.
The senator claimed some pact members were critical of Australia's lack of financial commitment to the Asia-Pacific pact, expressing concern that they may have been used as part of a greenhouse smokescreen that has enabled the US and Australia to bolster their public commitment to climate change strategies while refusing to adopt mandatory emissions reduction targets.
The APPCDC, founded in July 2005, lists the United States, Australia, India, China, Japan and South Korea as signatories to a cooperative agreement on the development and transfer of greenhouse emissions reduction technology.
The APPCDC members are said to produce at least half of the world's greenhouse gas emissions.
Membership to the APPCDC does not require mandatory emissions reduction targets, and other members of the Association of Southeast Asian Nations (ASEAN) have said they may sign the pact at a later stage.
Shortly after the climate pact was announced, foreign minister Alexander Downer said the Asia-Pacific climate pact was meant to "complement and not replace" the Kyoto Protocol, which both the US and Australia have refused to ratify due in part to the mandatory emission reduction targets.
The APPCDC was originally scheduled to meet in November 2005, before the UNFCCC conference in Montreal, but in October the members announced that they would delay the first meeting until January at the earliest.
Milne has criticised Australia's federal environment minister Senator Ian Campbell, saying he has placed undue emphasis on Australia's role in helping establish the APPCDC as proof of Australia's commitment to emissions reductions, given the member nations have not yet held their first meeting.
Milne said her discussions with delegates from other Asia-Pacific climate pact members had revealed international criticism of Australia's lack of funding for any specific project to date.
"Australia's credibility is on the line in January when a ministerial meeting of the Asia-Pacific climate pact will take place. If Australia fails to put money into specific project funding at that meeting, then the whole thing is likely to collapse," Milne said in Canberra yesterday.
"Its promise is to be involved in an informal dialogue and its wish list is the Asia-Pacific pact which remains no more than an unspecific promise of technology transfer."
Milne accused Campbell of having "dined out constantly" on Australia's APPCDC involvement after committing nothing more than a "wish and a promise".
While Australia and the US have been criticised for refusing to ratify the Kyoto protocol, placing emphasis on the APPCDC instead, other members of the Asia-Pacific climate pact are actively involved in other international climate change agreements, that benefit both the environment and open the doors to the emerging carbon-trading market, according to Milne.
"China and India are beneficiaries of the European Collaboration which has taken advantage of the Clean Development Mechanism under the Kyoto Protocol and has seen £350 million ($A819 million) invested in a new pilot coal carbon capture and storage facility in China," Milne said.
Milne said Australia was becoming increasingly isolated as the world moved to address climate change, putting Australia's business community and its capacity to address its own emissions increasingly at risk.
"The Howard Government is condemning Australia to backwater status in the global challenge of climate change," Milne said.
