As the global balance of economic and political clout shifts, the world of climate negotiations is no longer a simple standoff between developed and developing nations.
Some fear a growing divide within the developing bloc will see the voice of poor, climate-vulnerable nations increasingly drowned out, further complicating the quest for an Earth rescue plan.
"This year's talks have highlighted a growing divide between poor developing countries that stand to lose the most from the lack of action on climate change, and countries that seem willing to hold up progress for tactical reasons," summed up the Environmental Investigation Agency advocacy group.
With their growth powered by fossil fuel combustion, the developing world giants blame the West's long emissions history for the peril facing the planet today, and insist it carries a larger burden for fixing the problem.
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Some fear this tit-for-tat exchange is removing the focus from the bigger picture.
"We need to get back to the spirit of Durban, which promised a truly multilateral approach with ambitious contributions from all," Tony de Brum, Minister-in-Assistance to the Marshall Islands President, told AFP.
The Durban climate conference in 2011 had agreed on a new pact to be signed by 2015, for the first time binding all the world's nations to emissions curbs.
The goal is to limit average global warming to 2.0 degrees Celsius over pre-Industrial Revolution levels.
On current emissions trends, scientists warn the Earth could face warming of 4.0 C or higher -- a recipe for catastrophic storms, droughts, floods and land-gobbling sea-level rise that would hit poor countries disproportionally hard.
Wealthy countries stuck to their guns in Warsaw, saying developing nations must do their fair share given that China is now the world's biggest emitter of CO2, with India in fourth place after the United States and Europe.