Washington state Gov. Jay Inslee (D) signed a pledge Tuesday promising to reject donations from the fossil fuel industry ahead of a likely run for the White House that he’s vowed to uniquely center on climate change.

In an interview with HuffPost, Inslee, 67, said he added his name to the list of more than 1,300 politicians across the United States who took the No Fossil Fuel Money Pledge.

The vow, administered by a coalition of 16 left-leaning environmental groups, commits candidates to “adopt a policy to not knowingly accept any contributions over $200 from the PACs, executives, or front groups of fossil fuel companies — companies whose primary business is the extraction, processing, distribution, or sale of oil, gas, or coal.”

“This is just one small statement that they should not continue to have undue influence over our decision-making over the existential threat against our nation,” Inslee said by phone Tuesday night. “This challenge calls for the scale of national effort similar to when we went to the moon, similar to when we beat fascism.”

Inslee is the second governor to sign the pledge, following newly elected Minnesota Gov. Tim Walz (D). California Gov. Gavin Newsom (D), who was sworn in this week, took a similar pledge ― called Oil Money Out ― but the oath was limited to the oil industry in the Golden State. But Inslee is the third likely contender for the next Democratic presidential nomination to take the pledge, after Sens. Bernie Sanders (I-Vt.) and Jeff Merkley (D-Ore.).

“The Democratic Party has to put a candidate forward who will make it the primary commitment to get this stuff done,” Inslee said. “It can’t be put in just one of the baskets of many issues.”

By signing, Inslee is laying the groundwork for a historic, if long-shot, bid for the presidency on the single issue of scaling back planet-warming emissions and preparing for climate change. The move is bold but timely. Record-breaking storms, droughts and wildfires wreaked havoc across the U.S. over the past three years as President Donald Trump attempted to boost the fossil fuel industry by gutting or delaying nearly every major federal climate regulation.

Even amid a three-week partial government shutdown leaving federal workers scrambling for pay, the Trump administration is continuing to approve oil and gas drilling permits, Bloomberg reported.

Bloomberg via Getty Images An American flag flies on top of a Unit Drilling Co. rig in the Bakken Formation outside Watford City, North Dakota.

In October, United Nations scientists issued a dire warning, giving world governments a 2030 deadline to halve emissions or face a cataclysmic temperature spike. Yet emissions hit an all-time high last year and look set to continue soaring as new estimates released Tuesday showed a 3.4 percent surge in the United States alone.

A new generation of left-wing Democrats, including Reps. Alexandria Ocasio-Cortez (D-N.Y.) and Rashida Tlaib (D-Mich.), ran as champions of a Green New Deal, a sweeping federal policy to end fossil fuel use and guarantee high-wage clean-energy sector jobs to every American. It’s a popular idea. One poll released last month pegged the number of registered voters who support a Green New Deal at 81 percent, including 57 percent of conservative Republicans.

Yet only some of the high-profile Democrats hoping to challenge Trump in 2020 have made the issue a top priority. Sanders held a town hall on climate change in December and is preparing legislation on a Green New Deal. Merkley was the first senator to back a Green New Deal last year. Sen. Cory Booker (D-N.J.) followed soon after, explicitly tying his push for a federal job guarantee to the climate proposal.

Former Rep. Beto O’Rourke (D-Texas) and Sens. Kamala Harris (D-Calif.) and Elizabeth Warren (D-Mass.) voiced tepid support for the concept of a Green New Deal.

“The pledge, even more than the Green New Deal, represents a true litmus test for serious climate action in 2020 and beyond,” R.L. Miller, the president of the political action committee Climate Hawks Vote, said by email of Inslee’s announcement. “Our democracy is being drowned in a dark oily tidal wave of dirty money and it needs leaders who can rise above.”

Inslee stands alone as the first candidate to say climate change takes priority over other hot-button issues like health care, immigration and inequality.

“The political capital that needs to be invested, the intense gathering of allies to push this through Congress, just requires an all-out effort,” Inslee said. “That’s not going to be done just because somebody now decides they’re interested in climate change. It takes someone who’s frankly cared about it for years and years.”

Inslee boasts a lengthy record on climate.

In 2006, Inslee, then one of Washington’s 10 U.S. representatives, spearheaded an effort to set a renewable portfolio standard in the Evergreen State. In 2007, he co-authored a book called Apollo’s Fire: Igniting America’s Clean Energy Economy, which, as the title implies, laid out a vision for bolstering the renewable-energy and electric-vehicle industries. In 2009, he co-founded the Sustainable Energy and Environment Coalition in the House of Representatives. Later that year, he sponsored the federal cap-and-trade bill known as Waxman-Markey.

This is the 11th hour. But it should be our hour to shine. Washington Gov. Jay Inslee (D)

Since he was first elected governor in 2012, Inslee repeatedly championed incentives for electric vehicles, with the goal of getting 50,000 on Washington state roads by 2020. In 2016, he became the first governor to issue an executive order capping carbon dioxide emissions. A glowing profile published last week in The Atlantic credited Inslee with pursuing “arguably the most progressive and greenest agenda in the country, with fields of solar panels, fleets of electric buses, and massive job growth to show for it.”

In just the past year, Inslee kiboshed two major fossil fuel projects and added new regulations on existing infrastructure. Last January, he personally intervened to reject permits to build what would have been the nation’s largest oil-by-rail facility at the Port of Vancouver. He signed a bill in March putting a new tax on pipelines, forcing the operators to fund a state program to protect against oil spills. In May, he blocked construction of a $680 million coal-export terminal on the Columbia River.

“This is the 11th hour,” Inslee said of the time that’s left to halt catastrophic global warming. “But it should be our hour to shine.”

Inslee fought over the past year to pass Initiative 1631, a ballot measure that would have put a $15 per metric ton fee on carbon dioxide emissions and directed the money toward expanding public transit, energy-efficiency retrofits for big buildings and new wind- and solar-powered plants. The proposal, dubbed by some a state-level Green New Deal, failed after the oil industry spent a record $31 million pressuring Evergreen State voters to reject the measure. It was Inslee’s third attempt at putting a price on carbon in his state.

But Inslee said he’s not wedded to a carbon pricing scheme as the central focus of a climate policy. Carbon taxes are gaining favor among Republicans and oil companies. But a new gas tax triggered fiery protests in France and became a rallying cry over the past few months against carbon taxes that don’t directly benefit low- and middle-income workers.

ASSOCIATED PRESS A photo shows the smoky haze that obscured the Space Needle and downtown Seattle in August 2018.

“People have focused on this issue of a carbon tax, but it may not be necessary” to finance renewable energy infrastructure, Inslee said. “We may find other ways to finance this. You look at the Trump tax cuts that were misbegotten and gave all these tax benefits to the upper-income groups, and people weren’t worried about the deficit when they did that.”

Inslee faces some critics on climate change. In February, 13 young people in Washington, ages seven to 17, sued the state, alleging Inslee and the agencies under his control violated the constitutional rights of a generation by failing to curb greenhouse gas emissions. One plaintiff ― Jamie Margolin, a 17-year-old activist in Seattle who founded the youth climate group Zero Hour ― railed against Inslee in a series of tweets last week accusing the governor of fighting “tooth & nail” against the lawsuit, which a state judge tossed in August.

Margolin called Inslee “an old corperate [sic] establishment white man who screws over the youth and indigenous folks of his state.” She pointed to the ongoing fight over a massive liquefied natural gas terminal in Tacoma, Washington, which the Puyallup Tribe and leaders from 14 other Northwest tribes pleaded with Inslee to reject.

Asked about the accusations on Tuesday, Inslee said the Tacoma facility had already begun permitting and that his administration was “going to follow the law” and allow the process to play out, though he said he requested additional carbon dioxide analyses of the project.

“I cannot make statements about eventual permitting until that plays out,” he said. In a follow-up email, Inslee’s spokesman reiterated that the project “doesn’t have final permitting yet.”

Earlier this year, Inslee visited the scorched remains of Paradise, California, a town decimated by the state’s deadliest wildfire in history. He said that visit made clear to him that the 2020 election needed to be singularly focused on the crisis at hand.

“It looked like Dresden after World War II,” Inslee said. “In my final days, when I look back and ask what I did to deal with climate change, I want to be able to say I did everything I could, including possibly running for president.”