Story highlights The NRDC hasn't endorsed before in a presidential race

The group says Donald Trump has a 'big polluter agenda'

(CNN) The Natural Resources Defense Council Action Fund, a large environmental advocacy organization, announced on Tuesday that it was backing Hillary Clinton for president, the first time the group has made a presidential endorsement.

In a statement, the leadership of the NRDC Action Fund -- which is affiliated with but separate from the Natural Resources Defense Council -- praised Clinton's approach to environmental issues in announcing its "historic" endorsement.

"Hillary Clinton is an environmental champion with the passion, experience and savvy to build on President Obama's environmental legacy. More than any other candidate running, Hillary Clinton understands the environmental challenges America faces, and her approach to solving them is grounded in the possibility and promise our democracy affords," Rhea Suh, president of the NRDC Action fund, wrote.

And the environmental advocacy group's president took aim at presumptive Republican nominee Donald Trump, criticizing his "disastrous and frankly nonsensical environmental agenda -- suggesting that he would tear up the Paris Climate Agreement, and that there is no drought in California. His plan for his first 100 days would take us back 100 years, and America cannot afford to indulge in his climate conspiracy theories."

"It's time...to stand with Hillary Clinton and reject Donald Trump and his big polluter agenda."

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