1) CHINA (annual emissions of greenhouse gases: 6.8 billion tons, 5.5 tons per capita)
* Emissions - President Hu Jintao promised on September 22 that China would cut its carbon dioxide emissions per dollar of economic output by a notable margin by 2020 compared to 2005. The carbon intensity goal is the first measurable curb on national emissions for China. Hu reiterated a promise that China would try to raise the share of non-fossil fuels in primary energy consumption to 15 percent by 2020.
* Demands - China wants developed nations to cut their greenhouse gas emissions by at least 40 percent below 1990 levels by 2020 and to give far more aid and green technologies to developing nations.
2) UNITED STATES (6.4 billion tons, 21.2 tons per capita)
* Emissions - President Barack Obama wants to cut U.S. emissions back to 1990 levels by 2020 and by 80 percent below 1990 levels by 2050. For 2020, that means a 14 percent cut from 2007 levels.
We will press ahead with deep cuts in emissions to reach the goals that we set for 2020, and eventually 2050, he told the United Nations on September 23, adding that the days when the United States dragged its feet were over.
Democratic U.S. senators pushing legislation to cut emissions by 20 percent from 2005 levels say they are making progress -- the measure is expected to begin moving through a key Senate Committee in November. But many are skeptical that it can become law by Copenhagen
* Finance - The United States says a dramatic increase is needed in funds to help developing nations.
* Demands - We cannot meet this challenge unless all the largest emitters of greenhouse gas pollution act together, Obama said.
3) EUROPEAN UNION (5.03 billion tons, 10.2 tons per capita)
* Emissions - EU leaders agreed in December 2008 to cut emissions by 20 percent below 1990 levels by 2020 and by 30 percent if other developed nations follow suit.
* Finance - EU leaders have agreed that developing nations will need about 100 billion euros ($146.8 billion) a year by 2020 to help them curb emissions and adapt to changes such as floods or heatwaves. As an advance payment, they suggest 5-7 billion a year between 2010 and 2012.
* Demands - The EU wants developing nations to curb the rise of their emissions by 15 to 30 percent below a trajectory of business as usual by 2020.
4) RUSSIA (1.7 billion tons, 11.9 tons per capita)
* Emissions - President Dmitry Medvedev said in June that Russia's emissions would be around 10 to 15 percent below 1990 levels by 2020. That means a rise from now -- emissions were 34 percent below 1990 levels in 2007.
* Demands - Prime Minister Vladimir Putin said on September 11 that Russia would reject any new climate pact that imposed restrictions on Russia but did not bind other big polluters such as the United States or China.5) INDIA (1.4 billion tons, 1.2 tons per capita)
* Emissions - India is prepared to quantify the amount of greenhouse gas emissions it could cut with domestic actions to fight climate change, but will not accept internationally binding targets, Environment Minister Jairam Ramesh said on September 17. India has said its per capita emissions will never rise to match those of developed nations.
* Demands - Like China, India wants developed nations to cut emissions by at least 40 percent by 2020. Ramesh said on October 10 that nations should scale down ambitions for Copenhagen from exaggerated expectations.
6) JAPAN (1.4 billion tons, 11.0 tons per capita)
* Emissions - New Prime Minister Yukio Hatoyama wants to cut Japan's emissions by 25 percent below 1990 levels by 2020 if Copenhagen agrees an ambitious deal, toughening a goal set by the previous government of an eight percent reduction.
* Finance - Hatoyama told the United Nations on September 22 that Tokyo would also step up aid. Japan is prepared to offer more financial and technical assistance than in the past, in accordance with the progress of the international negotiations, he said.