WASHINGTON -- Buried in the text of yesterday's joint declaration between the President Barack Obama and Chinese President Hu Jintao was a significant climate announcement: The Obama administration will offer concrete emission reduction targets as part of next month's negotiations, as long as the Chinese offer a climate proposal of their own.

The question of whether the United States would identify a short-term emission goal has been one of the main sticking points in the United Nations-sponsored talks for nearly a year. Almost all industrialized nations, and many major developing countries, have announced how much they plan to curb their greenhouse gas output by 2020. Neither the United States nor China -- which is not obligated to do so under the U.N. framework, even though it now ranks as the world's biggest carbon emitter -- has done so, hampering the prospects of an agreement.

Just last weekend, the Obama administration endorsed a proposal by the Danish government to seek a political agreement on global warming in Copenhagen next month, which could be codified in 2010 as a legally binding international treaty. According to the joint declaration, "an agreed outcome at Copenhagen should ... include emission reduction targets of developed countries and nationally appropriate mitigation actions of developing countries."

Todd Stern, U.S. special envoy for climate change, said last week that any emission reduction target the United States adopts on an international level would be contingent on domestic legislation, which has yet to be finalized.

The House-passed climate bill includes a 17 percent reduction in greenhouse gases compared to 2005 levels; the Senate Environment and Public Works Committee has approved a 20 percent cut over the same period, but key senators such as Max Baucus, D-Mont., have vowed to lower that level.

Michael Levi, a senior fellow on environment and energy issues at the Council on Foreign Relations in Washington, said the U.S.-China declaration "has moved expectations up a bit for Copenhagen."

He said it was significant that the Chinese signed off on language saying any successful outcome in Copenhagen would "provide for full transparency" on greenhouse gas cuts.

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