WASHINGTON — A top Russian banker said Friday that his bank never had a role in a project once planned by the Trump Organization to build a tower in Moscow, despite an assertion by one of President Trump’s associates that the banker had helped finance the deal.

The banker, Andrey L. Kostin, said in an interview with The New York Times that he had never met Felix Sater, an associate of Mr. Trump’s who was working on the deal. In a 2015 email to one of Mr. Trump’s lawyers, Mr. Sater claimed that Mr. Kostin had agreed to finance a Trump building in Moscow. The deal was never finalized, and the building never built.

The Times reported in August that Mr. Sater had boasted in a series of emails to the lawyer, Michael Cohen, that he had close ties to the Russian president, Vladimir V. Putin. He said that building a Trump tower in Moscow would demonstrate Mr. Trump’s business prowess and help get him elected president. The emails were provided to the House Intelligence Committee in August as part of the panel’s inquiry into Russia’s attempts to disrupt last year’s election.

Mr. Kostin said a review by the bank’s security department of all emails and documents showed that Mr. Sater had no dealings with the bank. “We never, ever heard about this case,” Mr. Kostin said, adding: “It’s absolutely wrong information; it’s absolutely fake news.”