Ukraine's president and top security brass discussed ways to prevent leaks of military information at a meeting on Friday, Kyiv said, after secret documents detailing Western help for Ukraine reportedly ended up online.
A statement about the meeting issued by the president's office did not say a leak had occurred. It also did not refer to a New York Times report that said documents about US and NATO plans to build up the Ukrainian military had been leaked online.
"The participants of the meeting focused on measures to prevent the leakage of information regarding the plans of the defense forces of Ukraine," a presidency statement said, detailing other topics that participants also discussed.
The Times reported on Thursday that the Pentagon was investigating how documents about plans to build up Ukrainian forces before their planned counter-offensive against invading Russian forces were posted on social media channels this week.
Reuters was not immediately able to review the leaked documents.
A spokesperson for Ukrainian military intelligence said it was possible the information in the posts was entirely fictitious, and that there had been no leak.
A preliminary analysis of the posts indicated they were made up of false and distorted casualty figures, and that some of the information was drawn from open sources, the spokesperson, Andriy Yusov, said.
"We'll wait of course for official commentary (from the Pentagon), but I think the Ukrainian public has no grounds to worry," he said.
Ukrainian presidential adviser Mykhailo Podolyak told Reuters earlier that the posts looked like a Russian disinformation operation to sow doubts about the counter-offensive.
He said they contained a "very large amount of fictitious information" and that Russia appeared to be trying to seize back the initiative in its invasion, now in its 14th month.
"These are just standard elements of operational games by Russian intelligence. And nothing more," Podolyak said in a written statement.
Ukrainian troops have for months faced a Russian onslaught in its east that has focused on the city of Bakhmut. Kyiv hopes its forces can launch a counter-offensive in the coming weeks or months to wrest back occupied territory.
"Russia is looking for any ways to seize back the initiative," Podolyak said. "To try to influence the scenarios for Ukraine's counteroffensive plans. To introduce doubts, to compromise the ... ideas, and finally to intimidate (us) with how 'informed' they are."
The Times report said the documents appeared to have been modified in certain parts. One part offered an estimate for Ukrainian military losses that was far higher than Western estimates made available so far.
Ukraine does not disclose the scale of its losses and is very sensitive about the subject.
