Did Ukrainian President Volodymyr Zelenskyy embezzle $400 million from U.S. aid that had been allocated for the purchase of fuel? No, that's not true: There is no evidence that this has happened.
The claim appeared in a video (archived here) published on TikTok by the Belarusian account political.channel.minsk on April 13, 2023, under the title "New leak about Zelenskyy."
It opened:
Proven! Zelenskyy stole $400 million.
This is what the post looked like on TikTok at the time of writing:
(Source: TikTok screenshot taken on Tue Apr 25 07:31:28 2023 UTC)
The claim originated from an article published on Substack on April 12, 2023, by U.S. journalist Seymour Hersh under the title: "Trading with the enemy." The story was also featured on Russian TV and other Russian state media outlets.
According to Hersh (whose recent work has been controversial), "The Ukraine government, headed by Volodymyr Zelenskyy, has been using American taxpayers' funds to pay dearly for the vitally needed diesel fuel that is keeping the Ukrainian army on the move in its war with Russia." Hersh alleges that "the Ukrainian president and many in his entourage have been skimming untold millions from the American dollars earmarked for diesel fuel payments."
The information provided by Hersh in his Substack article has no credible source besides "one knowledgeable American intelligence official" whose name is not provided.
At the end of March 2023, during a Foreign Affairs Committee hearing on Oversight, Transparency and Accountability of Ukraine assistance, Inspector General of the U.S. Department of Defense Robert P. Storch announced that reports had not detected any instances of security assistance deviation, meaning that there was no evidence of funds being misused by the Ukrainian government. At a press briefing on March, 29, 2023, U.S. National Security Council Coordinator For Strategic Communications John Kirby mentioned that there was "no misconduct when it comes to managing the security assistance" to Ukraine. The U.S. Treasury Department has also said it had no indication that U.S. funds had been misused in Ukraine.