AP:

MEXICO CITY — Washington’s special climate envoy conceded Monday the U.S. may not have a climate and energy bill in place when the next major global warming conference is held in Mexico late this year, but insisted the legislation is not crucial to those talks.
Efforts to pass the long-stalled bill hit another setback this month when its only Republican sponsor, Sen. Lindsay Graham of South Carolina, withdrew his support.
“I hope to get it this year. If we don’t get it this year, we’ll keep pressing to get it next year,” Todd Stern, President Barack Obama’s climate envoy, told reporters during a visit to Mexico.
Some environmental groups including Greenpeace say drafting a new global treaty on climate change will be difficult unless the U.S. has a climate law in place. The planned bill would aim to cut U.S. emissions of carbon dioxide and other greenhouse gases 17 percent below 2005 levels by 2020.
Mexico is hosting the next round of international climate negotiations in December in Cancun.