Bush administration officials have issued strong objections to a proposed declaration on global warming to be issued during next month's Group of Eight economic summit.

In a draft statement obtained by U.S. media, administration officials are rejecting a proposal by German Chancellor Angela Merkel to cut greenhouse gas emissions below 1990 levels by the year 2050. They are also reported to be opposed to language to raise overall energy efficiencies by 20 percent by 2020.

Mrs. Merkel has proposed limiting the worldwide temperature rise this century to two degrees Celsius. Germany has offered to drop this in favor of a Russian proposal that targets a lower range, but The Washington Post says the U.S. has not accepted the modified language.

An official with the environmental advocacy group Greenpeace calls the Bush administration's objections "criminal, but not unexpected."

Representatives of the world's eight leading industrial nations have been negotiating over the statement in Germany, which is hosting the summit.