Buryakov was arrested in the United States on Monday on charges of 'conspiracy to act as an unregistered agent of a foreign government' and 'acting as an unregistered agent of a foreign government.' He is held in the Metropolitan Correctional Center in Manhattan.
"Buryakov categorically denies all charges against him. He hopes that the lawyers, selected for him by the [Russian] Vnesheconombank, will repudiate the unfounded and false accusations against him," the diplomats said.
The diplomats added that his custody conditions at the prison were "satisfactory."
Buryakov was arrested as part of an alleged Russian intelligence ring that the FBI says worked for Russia's Foreign Intelligence Service to gather economic information.
Two other Russian nationals, Igor Sporyshev and Viktor Podobny, were accused of working for Russia’s Foreign Intelligence Service along with Buryakov. According to the US Department of Justice, Sporyshev claimed he was a Russian trade representative, while Podobny stated that he served as an attache to Moscow’s mission to the United Nations.