City leaders from around the world gathered for an environmental summit hosted by former President Bill Clinton and New York Mayor Michael Bloomberg.
"It is in cities that the battle to tackle climate change will be won or lost," London Mayor Ken Livingstone said.
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. Organizers say cities bear a significant responsibility to address climate change because they cover less than 1 percent of the Earth's surface but are overwhelmingly responsible for polluting it, generating 80 percent of heat-trapping greenhouse gases.
"Our theme is not whether we should work together, because we know that we must, it is how and how fast we can do so," New York's Deputy Mayor Dan Doctoroff said.
The summit includes mayors from cities big and small from Seoul to Sao Paulo, from Albuquerque to Addis Ababa.
Participants said the meeting of local government officials comes at a crucial time, while many countries worldwide are struggling to have similar conversations that would lead to global and national standards for carbon reduction.
Just this week, U.N. delegates are meeting in Germany to gear up for a December gathering where negotiations will begin on a new set of international rules for controlling greenhouse gas emissions. The new accord would succeed the Kyoto Protocol, which ends in 2012.
And in June, the summit of the Group of Eight major industrialized countries the U.S., Britain, France, Germany, Japan, Italy, Canada and Russia will also meet in Germany, and climate change is a top priority on the agenda.
Meanwhile, mayors said Tuesday, that local governments cannot wait around.
"Where national governments can't or won't lead, cities will," Toronto Mayor David Miller said.
Conference organizers, who invited a number of CEOs and business leaders to this year's gathering, also said they hope to involve the private sector in the movement at the city level. They hope to convince companies that going green through innovative construction, transportation alternatives and other environmental changes is a profitable economic move.
The United States has imposed new sanctions against the Nord Stream 2 gas pipeline project, which still remains under construction