NEW CASTLE, N.H. (AP) — Joe Biden is looking voters in the eye and promising to “end fossil fuel.”

The former vice president and Democratic presidential candidate made the comment Friday after a New Hampshire environmental activist challenged him for accepting donations from the co-founder of liquified natural gas firm.

Biden denied the donor’s association to the fossil fuel industry before calling the young woman “kiddo” and taking her hand. He said, “I want you to look at my eyes. I guarantee you. I guarantee you. We’re going to end fossil fuel.”

The activist, 24-year-old Rebecca Beaulieu, later said she appreciated that Biden took her question seriously, but that he was not satisfied with Biden’s plan to eliminate net carbon emissions by 2050.

She also said she found Biden’s use of “kiddo” patronizing.