The U.S. government is investigating a leak of documents that include details of U.S. and NATO aid to Ukraine.
The handful of documents circulating on pro-Russian feeds on Twitter and Telegram resemble routine updates that the U.S. military produces daily but does not distribute publicly. They are dated from February 23 to March 1 and at least one of them was marked “top secret.” But they are not war plans and they provide no details on any planned Ukrainian counteroffensive.
U.S. Defense Department spokeswoman Sabrina Singh said late on April 6 that Washington is looking into the appearance on social media of leaked documents containing details of weapons deliveries to Ukraine, as well as battalion strengths and other sensitive information.
“We are aware of the reports of social-media posts, and the department is reviewing the matter,” Singh said.
The Pentagon has declined to comment on the authenticity of the documents. A leak of such sensitive material is highly unusual and troubling for Ukraine.
President Volodymyr Zelenskiy's office released a statement on April 7 about a meeting he had with his senior military staff, noting that “the participants of the meeting focused on measures to prevent the leakage of information regarding the plans of the defense forces of Ukraine.”
Ukrainian presidential aide Mykhaylo Podolyak told Reuters that the leak appeared to be a Russian disinformation effort aimed at undermining the planned counteroffensive. The leaked versions of the documents, Podolyak said, contain a large amount of fictitious information.
"Moscow is eager to disrupt a Ukrainian counteroffensive but it will see the real plans on the ground. Soon," Podolyak said on Twitter.
The documents include information about Ukraine’s use of munitions for U.S.-provided High Mobility Artillery Rocket Systems (HIMARS) and other advanced weaponry.
The New York Times, which first reported on the documents, called the leak “a big coup for Moscow” that could “harm intelligence sharing between Ukraine and the United States.”
Three U.S. officials told Reuters that Russia or pro-Russian elements are likely behind the leak.
The documents appear to have been altered to lower the number of casualties suffered by Russian forces, the U.S. officials said, adding that their assessments were informal and separate from an investigation into the leak itself.
One of the leaked documents said 16,000 to 17,500 Russian troops had been killed since Russia launched its full-scale invasion of Ukraine on February 24, 2022. The United States and Britain have estimated that the number of Russian casualties -- dead and wounded -- was approaching 200,000.
The officials spoke on condition of anonymity given the sensitivity of the matter and declined to discuss the documents in detail, Reuters reported. The news agency also said that the Kremlin and the Russian Embassy in Washington did not respond to requests for comment.