Living in Peace and Wisdom on our Planet

Other experts have estimated that China will only surpass the United States in coming years. The rise to number one emitter may put pressure on Beijing to do more to help a U.N.-led fight against global warming.

"China's 2006 carbon dioxide emissions surpassed those of the United States by 8 percent," the Netherlands Environmental Assessment Agency said in a statement. In 2005, it said China's emissions were 2 percent below those of the United States.

"With this, China tops the list of CO2 emitting countries for the first time," it said. Almost all scientists say rising amounts of carbon dioxide will bring more droughts, floods, desertification, heat waves, disease and rising seas.

The report, based on data on energy use and cement production, reckoned China's carbon dioxide emissions totaled 6.2 billion metric tons in 2006. Of the total, 550 million tons was from cement, a main source of industrial emissions.

U.S. emissions totaled 5.8 billion metric tons last year, of which 50 million tons was from cement, it said. The report said the European Union was in third place on the ranking ahead of Russia, India and Japan.

The International Energy Agency (IEA), which advises rich nations, said in April China was likely to surpass the United States as the top carbon dioxide emitter in 2007 or 2008.

The Dutch agency said its data were based on fossil fuel use estimated by BP, cement data from the U.S. Geological Survey and energy use data until 2004 from the IEA. Carbon dioxide accounts for about 75 percent of greenhouse gases.

China's economy has registered double-digit growth for four years in a row and expanded by 11.1 percent in the first quarter compared to a year earlier due to booming investments and exports.

China and other major developing nations have promised to do their "fair share" to curb greenhouse gases but say it is too early to talk of caps or cuts when rising energy use is key to helping hundreds of millions of people escape poverty.

Developing nations say countries with the highest per capita emissions should show the way. U.S. President George W. Bush has said China and other developing nation must do more.

With a population of 1.3 billion, China's per capita emissions are a quarter of those in the United States, with 300 million people.

The Group of Eight leading industrial nations agreed at a summit in early June to make "substantial cuts" in emissions and to try to work out a global treaty by 2009 to succeed the Kyoto Protocol. Kyoto binds 35 rich nations to cut emissions to 5 percent below 1990 levels by 2008-12.