In backing Hillary Clinton for president, a major environmental advocacy group said Tuesday a vote for Donald Trump would set the climate fight back 100 years.

For the first time ever, the NRDC Action Fund, a non-profit group engaged in political work in support of the fight against climate change, said it was endorsing a candidate for president.

"Hillary Clinton understands the environmental challenges America faces, and her approach to solving them is grounded in the possibility and promise our democracy affords us," NRDC Action Plan President Rhea Suh said in a statement.

Clinton during an April speech in New York said the issue of the environment, public health and economic equality were included under the same umbrella.

"Every child and every family in America deserves clean air to breathe, clean water to drink, and a safe and healthy place to live," she said in prepared remarks. "This a justice issue. It's a civil rights issue. And as president, it will be a national priority for us."

The NRDC said that, between Clinton and presumptive Republican nominee Donald Trump, only Clinton has endorsed a low-carbon agenda. Pointing to issues like the Flint, Mich., drinking water crisis, where lead has leached into the city's water supply, the NRDC Action Fund said pollution is often a more serious issue for poor and minority communities.

"Like us, she believes these communities deserve justice," the organization said in its endorsement.

Last week, Trump hammered home the Republican themes on energy during a keynote address before a petroleum council in North Dakota, the No. 2 oil producer in the country. If elected, Trump vowed to undo most of President Obama's climate issues, sign off on the Keystone XL oil pipeline from Canada and cancel the Paris Climate Agreement, an international effort to control climate change.

"If he wins, Donald Trump's plan for his first 100 days would take us back 100 years," Suh said. "His nomination by the Republican Party puts one of the most anti-environment presidential candidates in history a step closer to the Oval Office."

Adopting an American energy first platform, Trump said Clinton would wage war against the U.S. oil and gas industry, push the sector further away from coal and "unleash the Environmental Protection Agency to control every aspect of our lives." For the shale industry, Trump warned this could put the 2 million jobs expected in the next seven years in jeopardy.

The NRDC countered a low-carbon economy in the United States has already created "millions" of new jobs.

The group is affiliated with, but separate from, the Natural Resources Defense Council.