Mr. Telizhenko and Mr. Artemenko joined Mr. Giuliani in Washington in late November 2019 at the Washington studios of the conservative cable network One America News to record a series that the network claimed exposed corruption by the Biden family, and attacked “the impeachment hoax” as well as Mr. Mueller’s investigation.
Ahead of the December 2019 trip, Mr. Artemenko signed an agreement with Mr. Giuliani to help locate witnesses who would defend Mr. Trump, according to three people with knowledge of the contract, which Mr. Giuliani also signed. Mr. Artemenko was not paid for the work. Mr. Artemenko’s company later signed a lobbying contract to briefly represent Mr. Derkach in Washington.
In December 2019, Mr. Giuliani and a crew from the network traveled to Budapest and Kyiv to film interviews with current and former Ukrainian officials who claimed to have incriminating information about the Bidens and other Democrats.
Those who were interviewed included Mr. Derkach and two other men — another member of parliament and a recently fired Ukrainian prosecutor — who also ended up facing sanctions in January by the Treasury Department. The department described the two men, along with Mr. Telizhenko, as members of Mr. Derkach’s inner circle and accused them of advancing “disinformation narratives” to influence the 2020 presidential election.
It is unclear if Mr. Telizhenko is a focus of the Brooklyn criminal inquiry.
In an interview Thursday, Mr. Telizhenko rejected the accusations from the Treasury Department, saying that he had never met Mr. Derkach before Mr. Artemenko arranged the meeting over his objections. “I said, ‘This is not a good meeting,’” Mr. Telizhenko said he told Mr. Giuliani, adding that Mr. Derkach “was already toxic in Ukraine,” because “everybody knew that he was pro-Russian.”
About two months after the trip, Mr. Derkach traveled to New York and recorded a podcast with Mr. Giuliani, said Mr. Telizhenko, who added he later provided a voice-over translation for the interview.
In May 2020, after Mr. Biden had emerged as the presumptive Democratic presidential nominee, Mr. Derkach publicly released the first in a series of audio recordings of private telephone calls between Mr. Biden, during his time as vice president, and Petro O. Poroshenko, who was president of Ukraine.