President Bush called on the world's worst polluters to come together to set a goal for reducing the greenhouse gas emissions that are causing the climate to heat up. He didn't exempt his own country from the list.

"By setting this goal, we acknowledge there is a problem, and by setting this goal, we commit ourselves to doing something about it," Bush said in a speech that capped two days of talks at a White House-sponsored climate change conference. "We share a common responsibility: to reduce greenhouse gas emissions while keeping our economies growing."

He said each nation should establish for itself what methods it will use to rein in the pollution problem without stunting economic growth.

The gathering drew representatives from 16 nations, including big producers from the developing world like China and India as well as the European Union and United Nations. Bush's emphasis is on using green technologies and other voluntary efforts to tackle global warming. The president said the reduction goal should be finalized by next summer, along with ways to measure progress toward it.

He also proposed the creation of an international fund to finance research into clean-energy technology, announcing that U.S. Treasury Secretary Henry Paulson would coordinate the effort and would be in touch with other governments soon about moving forward.

"Each nation must decide for itself the right mix of tools and technology to achieve results that are measurable and environmentally effective," Bush said.

Bush's administration has seemed more sensitive of late to perceptions in other parts of the world that the U.S. government either does not take the phenomenom of global warming seriously — or not seriously enough.

It circulated among reporters covering this conference a pocket-size handbook aimed at dispelling "myths" it said exist about the U.S. environmental policy, including the notion that Bush refuses to admit that climate change is real and that humans are a factor.

The manual also calls it a myth that the United States is doing nothing to address climate change or that Bush's administration refuses to engage other nations on this issue.

U.S. emissions of greenhouse gases are estimated to constitute up to a quarter of the world's total output. Bush, urging China, India and the other biggest polluters to swap green technology, favors voluntary approaches to combating global warming.

His administration also has set about creating a process for more such talks and a possible long-term global goal for reducing emissions, with each nation permitted to draw up its own strategies and plans. Representatives attending the conference have expressed skepticism that not much more than talking and political goals might be accomplished. But they also seemed encouraged that the United States was at least willing to become part of the dialogue.

Until recently, said Emil Salim, an economist and member of the Indonesian president's council of advisers, Bush offered "no dialogue on the Kyoto Protocol whatsoever. This time, the members of the Kyoto Protocol are invited to discuss. So from that point of view, there is some improvement," he said in an interview. "But on the other hand, I think it has more to do with the domestic politics, because you have election."

Though Bush rejected the Kyoto Protocol, the U.N.-brokered international treaty intended to cut greenhouse gas emissions that is due to expire in 2012, he is seeking ideas for what should come next. Critics have said they fear he might use his talks to undermine the next round of negotiations in December in Bali, Indonesia.

But on Thursday, Secretary of State Condoleezza Rice and Paulson countered that the United States is serious about global warming and making progress to slow its growth rate in carbon dioxide and other industrial warming gases.

"I want to stress that the United States takes climate change very seriously, for we are both a major economy and a major emitter," Rice said. "Climate change is a global problem and we are contributing to it, therefore we are prepared to expand our leadership to address the challenge. That is why President Bush has convened this meeting."

They also gave reassurances that the U.S. intent is to contribute to the U.N. negotiations on climate change, even though those emphasize mandatory controls on carbon dioxide that Bush opposes. Bush rejected the Kyoto accord because he said it unfairly harmed the economies of rich nations like the United States and excluded developing nations like China and India from having to cut greenhouse gases.

"We want this year's U.N. climate change conference in Indonesia to succeed," Paulson said.

Bush's conference followed a U.N. meeting Monday at which Secretary-General Ban Ki-moon tried to build support among 80 world leaders for reaching agreement at the planned December talks. Other participants at the State Department conference were from Britain, France, Germany, Italy, Japan, Canada, Brazil, South Korea, Mexico, Russia, Australia and South Africa.

The meeting Thursday also drew about 70 demonstrators from Greenpeace and other environmental groups outside the State Department, where dozens were arrested for refusing to leave the premises after two hours of protest. The activists labeled the conference a fraud for not backing mandatory cuts in greenhouse gases.

The Bush administration proposes new "processes" and work teams for negotiating solutions. However, James Connaughton, who heads the White House Council on Environmental Quality, told the nations' representatives that their efforts must "be about more than presentations" and that "we need to take collective action to advance new technologies."

Yvo de Boer, the top U.N. climate official, told the 16 nations participating in the White House-led meeting that "this relatively small group of countries holds a key to tackling a big part of the problem" but that their response can succeed only by "going well beyond present efforts," especially among rich, industrialized nations.