Ukraine’s leaders say they don’t see a major U.S. intelligence leak as gravely damaging future offensives. A key reason: They have long held back on sharing their most sensitive operational information, doubting Washington’s ability to keep their secrets safe.

Ukrainian and U.S. officials said this week that only Ukrainians know some battle plans and other operational information, not the Americans, their most important ally. That means the leak of secret military documents, including some assessing Ukraine’s battlefield strengths and weaknesses against Russia, may not have been enough — so far — to change the course of the war.

“If military operations are planned, then only a very narrow circle of people know about the planning of the special operation,” Deputy Defense Minister Hanna Maliar said Wednesday on Ukrainian television. “The risk of leaks is very minimal” for the most important war matters.

Still, the U.S. sees the leaks as grave. The documents include previously unreported sensitive disclosures about Ukraine, South Korea, Israel, the United Arab Emirates and others. Senior Biden administration officials are working to stop the flow of classified information onto social media and websites and head off any lasting damage to relationships with allies and strategic partners.

And more damaging material could still surface. Leaked documents are continuing to appear online, and future revelations may be more detrimental to Ukraine than the ones that have been publicized so far.

Meanwhile, Russia is making clear that it is avidly studying each spilled secret. “Quite interesting,” Kremlin spokesman Dmitry Peskov said of the leaks.

Still, online Russian-language discussions groups showed Russian military bloggers arguing over whether the leaks themselves are U.S. disinformation, intended to mislead Russia by creating an impression that Ukraine’s military is vulnerable.

Ukrainian officials and ordinary Ukrainians have made clear they could afford no open split over the leaks with the United States, which has given Ukraine more than $100 billion in military and civilian support.

“It is a pity that such things happen,” said one woman, Nataliia Maltseva, in Kyiv, where many people said their thoughts were on matters other than the U.S. intelligence breach.

But “I trust Joe Biden, I know that he is an experienced person who loves Ukraine. I am sure that everything will only get better,” Maltseva said Wednesday.

Secrecy in one vital area, Ukraine’s plans for any upcoming offenses to repel Russian forces, remains unbreached, U.S. Defense Secretary Lloyd Austin told reporters in Washington on Tuesday after speaking with his Ukrainian counterpart.

“They have a great plan … but only President Zelenskyy and his leadership really know the full details of that plan,” the U.S. defense chief said.

Ukrainian civilian and military chiefs — speaking in European and North American capitals on their continual tours to round up the Western arms and cash to keep Ukraine’s fight going — responded to questions about whether the leaks would harm relations with the United States by saying that unity among allies was one of Ukraine’s most vital war needs.

The details disclosed “are not pleasant to hear,” Ukrainian Defense Minister Oleksii Reznikov told reporters in Madrid on Wednesday.

Data has ‘Lost its Relevance’

“There is a lot of information that is not true,” Reznikov added, without elaborating. “And the true information has already lost its relevance.”

He called the leaks a purposeful information operation, benefiting Russia, with an aim “to lower the level of trust between the allies.”

Concerns over the impact of the U.S. intelligence leaks came up “everywhere” in meetings with Ukrainian officials in Kyiv on Wednesday, said Sen. Joe Manchin. The West Virginia Democrat was accompanied by Sens. Mark Kelly of Arizona and Lisa Murkowski of Alaska as well as country music singer Brad Paisley on a one-day official visit that included meetings with President Volodymyr Zelenskyy and other top officials.

The leaks include photographs of paper documents creased by folding. U.S. defense officials say information on some of the papers has been altered.

The documents show real-time details from February and March of Ukraine’s and Russia’s battlefield positions and precise numbers of battlefield gear lost and newly flowing into Ukraine from its allies.

They also reveal just how close Ukraine’s vital air defense systems are to running out of missiles — with stocks expected to be exhausted as soon as late this month or May, absent significant resupply. That would open Ukraine’s skies to more of the Russian air and artillery strikes that already have devastated cities and infrastructure.

Ukrainian Prime Minister Denys Shmyhal, speaking to reporters in Toronto before arriving for talks with Austin in Washington on Wednesday, played down the danger, expressing optimism that Ukraine would get the new stocks of the Soviet-era air defense missiles it needs.

“Our air defense will be very effective,” Shmyhal told Canada’s CTV. “We will have all the equipment.”

Although the leaked information was more detailed, Ukraine and its allies have been warning publicly about the desperate resupply needs of Ukraine’s air defense system.

John Sipher, a former senior CIA official and expert on Russia, said while the leak of classified information is “despicable,” he doesn’t think it really hurts Ukraine’s war effort. The intelligence community’s most protected and sensitive secrets typically don’t wind up on the kind of Defense Department summaries that the documents appear to be, he said.

And since much of the information from Russia appears to come from signal intelligence — electronic monitoring of communication and weapons systems — “it is really hard for Russia to change its procedures and equipment on the fly during a war,” Sipher said.

Ukrainian presidential adviser Mykhailo Podolyak described the leaks regarding the war assessments as free of actual operational information, and partly fake. Ukraine’s strategy and tactics are developed by the military command and that work was not directly damaged, he told The Associated Press.

“Operations scenarios are still in development because the front line is flexible and changes are made every day,” he said.

Ever since Russia invaded in February 2022, U.S. officials are reported to have commented on how close Ukrainian leaders kept their war secrets. One common complaint was that the Americans knew more about Russia’s war status than they did about Ukraine’s.

On the streets of Kyiv, another Ukrainian, Serhii Bos, expressed hope that “our American partners” were learning from the breach, but he said it would have no impact on Ukrainians’ morale.

“Nothing changes,” he said. “Everything remains as it is. We need to reclaim our lands.”