WASHINGTON, April 27, 2009 (AFP) – Secretary of State Hillary Clinton said the United States “is ready to lead” and make up for lost time in the fight against climate change, as she opened an international forum here.

Hillary Clinton speaks at an Earth Day event (4/22/09)U.S. State Dept.“The United States is fully engaged and ready to lead and determined to make up for lost time both at home and abroad,” Clinton told a forum President Barack Obama set up to build political momentum for UN climate change talks in December in Copenhagen.

“The president and his entire administration are committed to addressing this issue and we will act,” she told the Major Economies Forum on Energy and Climate held at the State Department.

“The United States is no longer absent without leave,” she said alluding to widespread criticism that the preceding administration of president George W. Bush played down the threat from climate change and failed to do much about it.

For Clinton, there is no dispute about the evidence behind climate change.

“It is a threat that is global in scope but local and national in impact,” she said.

“We know climate change threatens lives and livelihoods,” she told envoys including foreign and environment ministers from 17 countries, the United Nations and the European Union.

“Desertificiation and rising sea levels generate increased competition for food, water and resources,” said the chief U.S. diplomat.

“But we also have seen the dangers that these trends pose to the stability of societies and governments. We see how this can breed conflict, unrest and forced migration,” she said.

“So no issue we face today has broader long term consequences or greater potential to alter the world for future generations,” she asserted.

Represented here are Australia, Brazil, Canada, China, the European Commission, France, Germany, India, Indonesia, Italy, Japan, Korea, Mexico, Russia, South Africa, United Kingdom, the United States, Denmark and the United Nations.

In introducing Clinton, Todd Stern, the U.S. special envoy on Climate, said: “We will be working hard because the stakes are high and time is short.”

The talks in Washington, which closed to the media after Clinton’s speech, are among several forums on the way to a UN meeting in Copenhagen in December aimed at sealing an international pact for curbing greenhouse gases beyond 2012.

That is when the Kyoto Treaty — rejected by Obama’s predecessor George W. Bush — is set to expire and be replaced by the Copenhagen deal.

The Bush administration maintained that Kyoto would be too costly for U.S. businesses to implement and called on developing countries to do more.