They claimed that a legitimate group of 33 businesses and environmental groups, the United States Climate Action Partnership, had agreed to slash emissions, blamed for warming the earth, by 90 percent by 2050 and had called for a moratorium on new coal plants.

US CAP includes oil majors ConocoPhillips, Shell Oil and automaker General Motors Corp.

The release said that US CAP was hoping to encourage decisive action in Bali, Indonesia, where delegates from about 190 countries are meeting to try to work out a broad long-term pact to fight climate change.

"We wanted to draw attention to US CAP's influence and hold them to taking real action on climate," Brian Jones, a spokesman for the tricksters who operated from Britain, Canada, Australia and the United States, said in an interview.

The group backed up their press releases by setting up Web sites for a phony public relations company and another claiming to be the new US CAP site, using its official logo.

US CAP businesses and environmental groups said the press release and pledge were "fraudulent."

In fact, at least one US CAP member, Duke Energy Corp , is hoping to build coal plants in the United States, and the group has pressured the US government to cut greenhouse gas emissions by only 60 to 80 percent by 2050.

News outlets including The Dallas Morning News and the New Zealand Herald put the story on their Web sites Monday, along with the false claims. A source at the Dallas paper confirmed that the site had been duped. The New Zealand paper could not be reached immediately.

"We really hope their editors do not hold them responsible for what was a political action," Jones said about reporters that had been fooled by the hoax.

Katie Mandes, a spokeswoman for the Pew Center on Climate Change, a member of US CAP, said, "We're taking the view that imitation is the highest form of flattery."

She said the group was looking into the legality of the hoaxsters' copying US CAP's logo.