Joe Biden on Friday forcefully defended his appearance the previous evening at a top-dollar campaign fundraising event in New York City that was held at the home of a supporter who helped found a natural gas company.

And standing right next to the environmental activist who challenged him for attending the fundraiser -- after he'd vowed not to take contributions from the fossil fuel industry -- Biden asked the young woman , whom he called “kiddo,” to “look in my eyes” as he pledged to wean Americans off fossil fuels by 2050.

BIDEN DEFENDS FUNDRAISER WITH FOSSIL FUEL COMPANY FOUNDER

Twenty-four hours earlier, the former vice president and frontrunner for the 2020 Democratic presidential nomination attended an event with donors co-hosted by Andrew Goldman – one of the founders of the Texas-based natural gas company LNG Western.

Former Vice President Joe Biden speaks with environmental activist Rebecca Beaulieu during a town hall in New Castle, New Hampshire on Friday, Sept. 6

On Friday, at a town hall in New Castle, N.H., with the Atlantic Ocean as a backdrop, 24-year-old environmental activist Rebecca Beaulieu from nearby Newmarket, asked Biden, "How can we trust that you’re going to act on the climate crisis if you’re still attending fundraisers that fossil fuel executives like Andy Goldman are at?”

'Here's the deal, folks'

Biden quickly denied there were any executives there, acknowledging that Goldman did co-found the company, “but he’s not on the board or any of it. He does not run it at all.”

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Democratic presidential candidate former Vice President Joe Biden pumps his fist as he speaks during a campaign stop, Friday, Sept. 6, 2019, in Laconia, N.H. (Associated Press)

But LNG Western still lists on its company website that Goldman is part of its “leadership” team and his LinkedIn profile lists that he still works for the company.

Biden then reiterated his pledge not to take contributions from fossil fuel companies, a vow that nearly every candidate in the record-setting field of Democratic White House contenders has also taken.

“Here’s the deal, folks. I have never taken money from the industry,” Biden told the crowd.

Biden highlighted his decades of work in trying to combat climate change, emphasizing “I’m incredibly proud of my record.” And he touted his climate change plan that he unveiled this summer, saying “it’s gotten rave reviews from the vast majority of all of the major environment groups.”

Then, moving in close and holding Beaulieu’s hand, he said “Kiddo. I want you to just take a look. You don’t have to agree. But I want you to look in my eyes. I guarantee you. I guarantee you we’re going to end fossil fuel … before 2050, God willing.”

Beaulieu later told reporters she appreciated that Biden seriously answered her question - but that she thinks his plan to eliminate net carbon emissions by 2050 wasn’t adequate.

She also said she found Biden's use of "kiddo" patronizing.

Blunt advice

Hours earlier, Biden received some blunt advise from one of his top supporters in New Hampshire. Longtime state Sen. Lou D’Allesandro, known as the ‘Lion of the state Senate,’ met one-on-one with the former vice president ahead of Biden’s town hall Friday afternoon in Laconia, N.H.

D’Allesandro - who has known Biden for years and last month endorsed the former vice president’s White House bid -- said that he urged Biden to be more concise on the campaign trail.

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“I said that he’s got to leave them wanting more and be specific and right on point. He’s got a great message but he’s got to condense it and get it out there,” D’Allesandro told Fox News and the Concord Monitor.

Asked if Biden agreed with his critique, D’Allesandro noted, “I think he concurred. He understood what I was saying, clearly.”

The state senator stuck around for the town hall – where Biden spoke and answered questions from the audience for just over an hour.

Asked if Biden was concise during the event, D’Allesandro said, “I think there were moments he was concise and the people appreciated that. But there were other times when he was way too long.”