Secretary of State John Kerry at the United Nation's COP 21 climate change conference in Paris. (AP photo)

(CNSNews.com) – Secretary of State John Kerry says the climate change deal he helped broker in Paris was the Obama administration’s most “important” accomplishment in 2015.

“As one year gives way to the next, international leaders have an opportunity to build on several major achievements of 2015,” Kerry wrote in an oped published Tuesday in the Boston Globe in which he also listed the nuclear deal with Iran, signing the Trans-Pacific Partnership, and normalization of diplomatic relations with Cuba.

“Of these, none is more important than the recent global agreement in Paris to prevent the most harmful impacts of climate change.” Kerry wrote.

Kerry credits the administration’s “reaching out to China, the world’s leading emitter of greenhouse gases,” as a cornerstone of the success of the United Nation’s climate change agreement,

“We have a shared responsibility now to sustain the momentum generated in Paris, so that the targets established there are considered not a ceiling on what we can accomplish, but rather the platform upon which we can make further gains,” Kerry wrote.

President Barack Obama and federal officials agreed to give $3 billion in funding to the U.N.'s Green Climate Fund to help developing nations - including China and India, which produce more greenhouse gases than industrialized nations - deal with the effects of climate change.

Earlier in the month, Kerry defended the climate change agreement against criticism from former NASA scientist James Hansen, who called it “a fraud really, a fake.... It’s just worthless words.”

“I understand the criticisms of the agreement because it doesn’t have a mandatory scheme and it doesn’t have a compliance enforcement mechanism. That’s true,” Kerry said on ABC’s This Week.

“But we have 186 countries, for the first time in history, all submitting independent plans that they have laid down, which are real for reducing emissions. And what it does, in my judgment, more than anything else, there is a uniform standard of transparency. And therefore, we will know what everybody is doing.”

Kerry began his commentary by comparing the Obama administration to the New England Patriots football team, which clinched the top spot in the AFC East with a 12-3 record.

“One reason for the remarkable record of the New England Patriots is the team’s single-minded focus on the next game,” Kerry wrote.

“Managing world affairs requires the same concentration on future challenges, for past accomplishments provide no guarantee of continued success. They can, however, lend confidence that, with the right preparation and effort, positive results will follow,” he said.

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