Two weeks of bickering among 192 nations over the future of a still-theoretical future regime to curb climate change ended Friday with little more than a partial agenda.

Observers said the inability to agree on a full work plan for the next three years to develop the global climate deal that nations in Durban, South Africa, last year promised would be ready for signatures by 2015 and ready to implement by 2020 underscores the still-deep divisions between nations.

"The difficulties at this meeting reflect the fact that many parties are getting their bearings in this new context," said Jonathan Pershing, the lead U.S. negotiator at the mid-year U.N. treaty talks in Bonn, Germany. Discussion over agenda, he noted, "is a much more substantive exercise. People are talking about how they perceive their interests."

China, for example, argued these past weeks that the Durban Platform, which calls for the future agreement to bind all major emitters to carbon cuts, should not be lumped together with existing commitments for emissions cuts. Its concern, negotiators said, was that it and other nations considered to be "developing" would be swept into new rules that legally obligate them to cut carbon before the agreed-upon year of 2020.

The United States and European Union, meanwhile, accused China of obstructing attempts to launch a negotiating track and slowing movement. China in turn told Agence France-Presse that rich countries were playing "dirty communications politics" and were themselves to blame.

In wrapping up the Bonn talks Friday, Pershing said he was not aware of China's specific accusations, but said, "I certainly would reject the notion that in any sense the U.S. has been a broker of things other than the most effective and aggressive efforts to proceed in this process."

Environmental groups also pinned the blame on industrialized countries, saying they are not moving fast enough to cut emissions or improve the pledges most made at the 2009 Copenhagen, Denmark, climate summit.

"Developed countries came absolutely empty-handed," said Celine Charveriat, director of campaigns and advocacy for Oxfam. She criticized Canada for pulling out of the 1997 Kyoto Protocol, the European Union for failing to increase its target of curbing carbon 20 percent by 2020, and Australia and New Zealand for failing to submit new Kyoto targets.

A growing 'ambition gap'?

She characterized the United States as "demanding a lot, but seriously dragging its feet and having nothing to offer." Meanwhile, she said, no new countries had come forward to pledge money for the Green Climate Fund, which is being designed to help poor countries meet climate needs.

"If you want to be in a position to push other countries who have a lot of people still living in poverty to do more, what signal are you giving? What is your credibility?" Charveriat said.

Activists also noted, though, that countries agreed on the need for a work plan to address the "ambition gap" between global pledges and what is really needed to keep the world from catastrophic warming.

"At the very least, there is space for countries to talk about raising the level of ambition before 2020, which is one of the biggest problems we have," said Nira Amerasinghe, an attorney at the Climate Change Program at the Center for International Environmental Law. "We just might be in a position in Doha to get an outcome that will put us in a space with positive results."

The next major U.N. conference will be held in Doha, Qatar, from Nov. 26 to Dec. 7. Pershing said that despite a "frustrating" first meeting of the year, he also expects the Doha conference to move the new treaty plans significantly forward.

"I don't think we've started badly," he said, adding that the protracted fight in Bonn "doesn't necessarily reflect in any fashion our ability to reach an agreement."

"My sense is, we will conclude this agreement in the next four years and we will have an outcome, but it will be difficult along the way," he said.