President Bush, seeking to blunt international criticism of the U.S. record on climate change, on Thursday urged 15 major nations to agree by the end of next year on a global emissions goal for reducing greenhouse gases.

Bush called for the first in a series of meetings to begin this fall, bringing together countries identified as major emitters of greenhouse gases blamed for global warming. The list would include the United States, China, India and major European countries.

The president outlined his proposal in a speech ahead of next week's summit in Germany of leading industrialized nations, where global warming is to be a major topic and Bush will be on the spot.

The United States has refused to ratify the landmark 1997 Kyoto Protocol requiring industrialized countries to reduce greenhouse gases to 1990 levels by 2012. Developing countries, including China and India, were exempted from that first round of cuts. Bush rejected the Kyoto approach, as well as the latest German proposal for what happens after 2012.

"The United States takes this issue seriously," Bush said. "The new initiative I'm outlining today will contribute to the important dialogue that will take place in Germany next week."

Along with his call for a global emissions goal, Bush urged other nations to eliminate tariffs on clean energy technologies.

Germany, which holds the European Union and Group of Eight presidencies, is proposing a so-called "2-degree" target, whereby global temperatures would be allowed to increase no more than 2 degrees Celsius — the equivalent of 3.6 degrees Fahrenheit — before being brought back down. Practically, experts have said that means a global reduction in emissions of 50 percent below 1990 levels by 2050.

Instead, Bush called for nations to hold a series of meetings, beginning this fall, to set a global emissions goal. Each nation then would have to decide on how to achieve the goal, White House officials said.

"The United States will work with other nations to establish a new framework for greenhouse gas emissions for when the Kyoto Protocol expires in 2012," the president said.

"So my proposal is this: By the end of next year, America and other nations will set a long-term global goal for reducing greenhouse gases. To develop this goal, the United States will convene a series of meetings of nations that produce the most greenhouse gasses, including nations with rapidly growing economies like India and China.

"Each country would establish midterm management targets and programs that reflect their own mix of energy sources and future energy needs," he said. "In the course of the next 18 months, our nations will bring together industry leaders from different sectors of our economies, such as power generation, and alternative fuels and transportation."

Bush's critics were quick to respond, even before the president's speech had concluded.

Daniel J. Weiss, climate strategy director for the liberal Center for American Progress, said the Bush administration has a "do-nothing" policy on global warming despite U.S. allies' best efforts to spur U.S. reductions.

"Our allies' pleas for action add to the voices of many big corporations such as Dow, Shell, General Electric, and General Motors," Weiss said. "These and other Fortune 500 companies endorsed a 60 percent to 80 percent reduction in global warming pollution by 2050, the level scientists indicate that we must reach to stave off the worst impacts. Unfortunately, these appeals from his foreign and corporate allies continue to fall on President Bush's deaf ears."

The U.S. last year actually experienced a drop in emissions of carbon dioxide, the heat-trapping gas most blamed for global warming. The 1.3 percent decline from 2005, the first drop in 11 years, was due to a mild winter followed by a cool summer.

Carbon dioxide is produced from burning fossil fuels, including natural gas and coal, which are used widely to produce electricity to heat homes in winter and run air conditioners in summer.

While Bush announced his new proposal, the administration registered its opposition to a number of approaches to combat global warming. Specifically, the White House said it does not support a global carbon-trading program allowing countries to buy and sell carbon credits to meet limits on carbon dioxide levels. The White House also expressed opposition to energy efficiency targets advocated by the EU, arguing that a standard applicable in one country does not fit another.