The formal withdrawals come only days aftre WCI announced the formation of a non-profit organization to administer the WCI greenhouse gas cap-and-trade program and service its technical needs. (See GLOBE-Net article " Western Climate Initiative Creates Non-Profit Corporation")

Only California of the US and four Canadian provinces - British Columbia, Manitoba, Ontario and Quebec - remain with the proposed carbon trading initiative.

And even B.C. has not committed itself to joining WCI's cap-and trade system that would limit the amount of greenhouse gas emissions companies could release, and require them to purchase carbon credits for emissions over that limit.

"We haven't made a final decision at this point," B.C. Environment Minister Terry Lake said in an interview with the Vancouver Sun Thursday, referring to cap-and-trade. "What we want to do is leave our options open, we want to make sure we don't rule out any options for B.C."

Arizona and the other US states formerly associated with the WCI have now clarified that they are no longer associated with the organization, but they will work with 13 other states and four Canadian provinces in a new initiative called North America 2050, which aims to spur energy innovation and create economic opportunities while reducing carbon emissions.

Arizona was a founding member of the WCI in February 2007 under former Democratic Governor Janet Napolitano.

"I think we all share a common commitment to create a cleaner, healthier environment," said Arizona Department of Environmental Quality Director Henry Darwin. "We may have different ideas about how to reach the goal, but we can learn by sharing success stories and by working together on policies we can agree on."

The new organization aims to collaborate on topics such as exploring carbon capture and sequestration and developing high quality offsets that may be used in emissions trading programs.

Participating jurisdictions in North America 2050 will be free to choose which policies and programs they want to be involved with based on their own priorities and vision, Darwin said.

"This new collaboration gives states and provinces the ability to lead and influence the evolving climate and energy policies in our respective countries," he said. "For Arizona, the emphasis is on finding ways to create jobs and stimulate the state economy through technological advancements in the clean energy sector."