Joseph R. Biden Jr. seemed momentarily caught off guard on Wednesday in a nationally televised climate change forum about whether a host of a fund-raising event for him had ties to the fossil fuel industry. Mr. Biden, who has pledged not to take money from oil and gas executives, was confronted by an audience member about a high-dollar fund-raiser on his schedule on Thursday in New York with an executive named Andrew Goldman.

Mr. Biden denied Mr. Goldman was a fossil fuel executive. The pledge he signed binds him not to take contributions of more than $200 from “S.E.C.-named executives of fossil fuel companies.’’ The former vice president told the CNN host Anderson Cooper that Mr. Goldman was not listed as an executive in fossil fuel company filings with the Securities and Exchange Commission. “That’s what we look at,’’ Mr. Biden said.

Mr. Cooper, who seemed apprised in advance of the issue raised by the audience member, pressed Mr. Biden, saying Mr. Goldman “has a company called Western LNG” that announced it was building an offshore terminal in western Canada to export natural gas. Earlier in the day, the news site The Intercept had reported on Mr. Goldman’s background.

“Well, I didn’t realize he does that,’’ Mr. Biden replied. “I’m going to look at what you just told me and find out if that’s accurate.’’