HEILIGENDAMM, Germany -- Leaders of the world's richest industrialized nations agreed here yesterday to a compromise on efforts to combat global warming that had been sought by President Bush.
Participants in the Group of Eight summit, led by German Chancellor Angela Merkel, yielded to Bush's insistence that while new talks were necessary to deal with climate change, the summit must not order specific steps and targets to reduce the greenhouse gases widely blamed for rising temperatures. Bush has sought goals rather than mandatory steps.
Merkel entered the summit calling for a plan endorsed by most European leaders, under which participating nations would reduce their emissions by 2050 to half what they were in 1990.
Instead, she came away with a goal, a nonmandated course favored by Bush, of such an emissions reduction, and a decision to "invite" the "major economies," a category that includes China, India and Brazil, to join them.
The United States had threatened before the meeting to reject large parts of the German proposal, which reaffirmed the role of the United Nations as the primary forum for negotiating climate agreements.
The agreement reached yesterday does not include a mandatory 50 percent reduction in global emissions by 2050, a key provision sought by Merkel; neither does it commit the United States or Russia to specific reductions.
"If you think of where we were a few weeks ago, and where we have reached today, this is a big success," Merkel said.
"One of the features I think we all agreed to is, there needs to be a long-term global goal to substantially reduce emissions," Stephen J. Hadley, the White House national security adviser, told reporters. "There are obviously a number of ideas as to how that should be done."
While the German chancellor and British Prime Minister Tony Blair presented the global warming agreement as a strong step forward, many environmentalists were not pleased.
Reinhard Buetikofer, head of Germany's opposition Green Party, said the summit statement was "juggling with words," and added: "To 'consider seriously' halving the emissions by 2050 is a triumph of vagueness and noncommitment."
At the same time, Fred Krupp, who heads the U.S. organization Environmental Defense, praised Bush's acceptance of the summit plan. He said Sen. Barbara Boxer, who leads the Senate Environment Committee, and House Speaker Nancy Pelosi, both California Democrats, must promptly take advantage of widespread U.S. business support for a cap-and-trade program, under which polluters that have difficulty reducing emissions to capped levels can buy credits from others who reduce emissions below the limit.
Such a system is in use in Europe under the Kyoto Protocol, which expires in 2012. The new plan proposed here would replace that U.N.-sponsored agreement.
Global warming was one of the central topics of the 2 1/2 days of formal and social meetings at the summit, whose participants are the United States, Russia, Germany, Britain, Canada, France, Italy and Japan.
For the second consecutive day, demonstrators opposed to economic globalization and in favor of tougher steps to counter global warming wreaked havoc with access routes to this village on Germany's northeastern coast, but failed to disrupt the session.
Greenpeace sent speedboats into the coastal security zone, 13 miles wide and nine miles out to sea, bringing police boats into pursuit. Two Greenpeace activists and one police officer were injured when an inflatable police boat ran over a Greenpeace boat, police said.
Twenty-one people were arrested, and police said they seized eight boats. Greenpeace said 11 boats were taken.
On land, about 5,000 demonstrators tried to reach a checkpoint near Heiligendamm, but were pushed back by mounted police.
James Gerstenzang writes for the Los Angeles Times. The New York Times contributed to this article.