Washington, May 6 (DPA) US emissions of carbon dioxide tumbled seven percent in 2009, government figures have showed, marking the largest one-year decline in the heat-trapping gas blamed for global warming since records began in 1949.

The Energy Information Administration (EIA) Wednesday attributed the sharp fall to a drop in energy use as the United States battled through its worst recession in decades, coupled with a smaller 2.3-percent drop in the "carbon intensity" of energy sources.

US carbon pollution had fallen annually on average just 0.9 percent over the last decade, amid improved energy efficiency and a slow transition to cleaner energy sources. Carbon-dioxide emissions rose 1.4 percent per year during the 1990s, according to the EIA.

The US and China together emit about 40 percent of the world's greenhouse gases, in which carbon dioxide is the chief component.

President Barack Obama has pledged to reduce US emissions by 17 percent below 2005 levels by 2020, but legislation toward that goal has stalled in the Senate.