NEW YORK - City leaders from around the world declared at an environmental summit yesterday that they could no longer wait for national governments to reverse global warming and instead must find solutions on their own.

Mayors from Seoul to Sao Paulo and Albuquerque to Addis Ababa gathered at the summit, hosted by New York Mayor Michael Bloomberg and former President Bill Clinton, to exchange ideas on how their cities have gone green.

"We cannot sit around and watch our environment deteriorate and put this world in jeopardy," Bloomberg said. "The public wants action, and if you have a void, the mayors are going to fill that void."

Mayors and local leaders from more than 30 cities kicked off the conference, known as the C40 Large Cities Climate Summit, which first met in 2005 in London. Clinton did not attend yesterday but was expected to be there today.

Organizers say cities bear a significant responsibility to address climate change because they generate 80 percent of heat-trapping greenhouse gases but cover less than 1 percent of Earth's surface.

"It is in cities that the battle to tackle climate change will be won or lost," London Mayor Ken Livingstone said.

The meeting comes as many countries are struggling to address global and national standards for carbon reduction. This week, U.N. delegates are meeting in Germany to gear up for December negotiations on a new set of international rules for controlling greenhouse-gas emissions. They would succeed the Kyoto Protocol, which ends in 2012.

When the Group of Eight major industrialized countries - the United States, Britain, France, Germany, Japan, Italy, Canada and Russia - meet in Germany in June, climate change will be on the agenda.

Meanwhile, the mayors said yesterday, municipalities cannot wait around.

"Where national governments can't or won't lead, cities will," Toronto Mayor David Miller said.

Philadelphia's next mayor was obviously not in

New York. But candidates' views are summarized at