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As President Obama rushes to cement his climate legacy, other nations are questioning whether his administration can make good on its promise to slash greenhouse-gas emissions ahead of a major climate summit in Paris at the end of this year.

"Certainly...countries want to get reassurance that the U.S. can deliver on what we've said that we're doing," U.S. special envoy for climate change Todd Stern told reporters Monday when asked about challenges to the Environmental Protection Agency's efforts to regulate carbon pollution from power plants. "I wouldn't say it's a big drumbeat, but I have definitely been asked that."

But Stern was quick to say that the efforts to curb greenhouse gases are "based fundamentally on existing legal authority" under the Clean Air Act and that "we have a very solid basis for...having confidence in the power plant rule and other regulatory steps that we've taken." Stern noted that EPA has a strong track record in emerging with the upper hand when faced with attack. "These kinds of EPA regulations have been repeatedly challenged over time and almost always upheld."

Stern added that "countries see what President Obama is doing, and what the administration is doing and have a fair, and I think justified degree of confidence that we can deliver." 

Legal challenges and political attacks faced by the regulations, which stand as a major pillar of the U.S. climate pledge, highlight the uncertain fate of Obama's most ambitious action to tackle global warming. 

Senate Majority Leader Mitch McConnell has urged states not to comply with the regulations and signaled that the international community should be wary of any kind of climate commitment made by the U.S. Just last week, the regulations endured their first major legal challenge when a federal appeals court heard oral arguments in litigation that takes aim at the rule.

U.S. negotiators plan to use the president's action as leverage to prod countries, including China, India, and Brazil, to make strong climate commitments of their own as part of a global climate deal.

Stern said that he did not get asked about challenges to the regulations during the Major Economies Forum on Energy and Climate, an event in Washington that wrapped on Monday. Seventeen nations belong to the forum, including Australia, Brazil, Canada, China, and India.

This story has been updated.

This article is from the archive of our partner National Journal.

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