China, the United States, the European Union, Russia and India are top world emitters. Targets they set will go a long way to decide the ambition of a new UN deal to fight global warming due to be agreed in Copenhagen in December.

Rich nations' plans cluster around cuts of roughly 15% below current levels by 2020. Many developing nations are trying to slow the rise of emissions, without caps that they say would stifle economic growth and their drive to end poverty.

DEVELOPED NATIONS UNITED STATES - President Barack Obama favors cutting US emissions to 1990 levels by 2020 -- about 15% below recent levels -- and by 80% below 1990 by 2050.

EUROPEAN UNION - European Union leaders agreed in December to cut emissions 20% below 1990 levels by 2020, a cut of about 14% from recent levels. EU leaders want rich countries to aim to reduce emissions by 60 to 80% by 2050 from 1990 levels.

* Britain has committed to a legally binding target to cut greenhouse gases by 80% below 1990 levels by 2050.

* Germany plans to cut carbon dioxide emissions by 40% by 2020 compared to 1990 levels.

* RUSSIA - Has not yet set a 2020 goal.

* JAPAN - Plans to outline 2020 cuts by June. The opposition Democratic Party has promised to cut emissions by 25% below 1990 levels by 2020 if it wins an election due by October.

* CANADA - Aims to cut emissions by 20% below 2006 levels by 2020 and envisages cuts of 60 to 70% below 2006 by 2050. Emissions are now more than 20% above 1990 levels.

* AUSTRALIA - Aims to cut emissions by 5% below 2000 levels by 2020 and by 15% below 2000 if there is a strong UN pact.

DEVELOPING NATIONS

CHINA - A 2006-10 plan aims to reduce energy consumption per unit of gross domestic product by 20%, curbing the rise of greenhouse gas emissions

. Beijing also plans to quadruple gross domestic product between 2001 and 2020 while only doubling energy use.

INDIA - New Delhi says priority must go to economic growth to end poverty while shifting to clean energies, led by solar power. A climate plan last June set no greenhouse caps but said per capita emissions will never exceed those of rich nations.

BRAZIL - Plans measures including halving Amazon deforestation over 10 years to avert 4.8 billion tonnes of emissions of carbon dioxide, energy conservation and sustaining the share of renewable energies. Hydropower alone accounts for 77% of electricity generation.

INTERNATIONAL TARGETS

THE KYOTO PROTOCOL - Binds industrialized nations except the United States to cut emissions on average by at least 5% below 1990 levels by 2008-12.

GROUP OF EIGHT – Leading industrial nations agreed at a G8 summit in Japan in July 2008 to a "vision" of cutting world emissions of greenhouse gases by 50% by 2050.

GLOBAL - About 190 nations agreed last year to work out a new treaty by the end of 2009 to succeed Kyoto, comprising deeper emissions cuts by rich nations and action by poor countries to slow their rising emissions.