Caught unaware by Ukraine’s surprise military incursion into Russia early this month, the Biden administration is still debating whether to help Kyiv’s forces hold and perhaps even expand the sliver of territory they now occupy in Russia’s Kursk region.

The Pentagon has asked the Ukrainians what they need to make their gambit successful, U.S. officials said, but no decisions have been made to materially support the effort.

Internal administration discussions have focused on whether to adjust the contents of weapons packages that are now being dispatched every two weeks, to include more armored vehicles or to speed up delivery of certain munitions and other equipment that could help the Ukrainians “dig in and defend themselves” in the nearly 500 square miles of Russian territory Kyiv now says it holds, a U.S. official said.

The Biden administration has previously prioritized rushing some weapons to Ukraine as battlefield conditions have changed, including replenishing air defense ammunition when Russia ramped up its aerial bombardments of Kyiv and other cities.

The latest shipment, $125 million worth of supplies announced Friday by Secretary of State Antony Blinken, includes howitzer and artillery ammunition, ambulances and medical equipment, TOW antitank missiles, and unmanned aerial systems and ammunition — all of which is badly needed in the ongoing fight against Russian forces in eastern Ukraine.

But as discussions continue over aid to the Kursk offensive, two issues have dominated. The Americans say they are unsure of Kyiv’s overall offensive strategy, and Ukraine’s dependence on U.S. weaponry has revived fears of direct U.S. and NATO escalation with Russia.

So far, the administration says it has no firm sense of Ukraine’s goals in seizing territory inside Russia, or whether it intends to hold or expand its occupation. “They may have a plan, but they’re not sharing it with us,” said the U.S. official, one of several who discussed internal administration assessments and deliberations on the condition of anonymity.

Asked Thursday why the administration has not voiced unalloyed support for the action in Kursk, Pentagon deputy spokesperson Sabrina Singh told reporters that officials are still trying to understand how Kyiv’s surprise offensive “fits into their strategic objectives on the battlefield itself. … We’re still working and still have some questions.”

While U.S. and Ukrainian officials publicly tout a strong relationship, their ties have been repeatedly tested throughout the 2½-year war by frustrations and fundamental disagreements about strategy and the level of support the West should provide.

Last year, as the counteroffensive against Russian forces turned into a bloody slog, Ukrainian officials and commanders vented that the Pentagon’s guidance on how to fight was largely academic and did not acknowledge the realities of battling a bigger, entrenched foe. Disagreements on a path forward prompted breaks in communication, including during a crucial period last summer when the top commander of U.S. forces in Europe, Gen. Christopher Cavoli, according to U.S. officials, could not reach Ukraine’s then-military chief, Gen. Valery Zaluzhny.

Despite not being informed in advance — and worried about the overall strategy — some U.S. administration and military officials have expressed admiration for how Ukrainian forces have managed the Kursk incursion, noting that they used some of the U.S. tactics that they were unwilling or unable to apply in last year’s counteroffensive.

“I think General Cavoli said we’ve been quite pleased with the way it’s going, as I think the Ukrainians have,” Christopher P. Maier, the assistant defense secretary for special operations and low-intensity conflict, told the Defense Writers Group on Friday. “I think at some level, it shows once again sometimes the fragility of the Russian military security infrastructure, that they were seemingly unprepared for such an event.”

Since last summer’s fraught counteroffensive, Ukrainian officials and new commanders have opted for a tighter circle of secrecy in Kyiv. U.S. officials said that, while they had detected Ukrainian troop movements around the border city of Sumy, the Ukrainians did not share their plans in advance.

Questions have also been raised inside the administration about the use of American weapons inside Russia, an apparent violation of stated U.S. policy — designed to avoid escalation between Moscow and Washington — that they are only for defense against Russian attacks on Ukrainian territory.

“There’s been no change to guidance we’ve given to Ukraine about where and how they can use U.S. weapons to defend themselves just across the border,” National Security Council spokesman John Kirby said Friday. Citing President Joe Biden’s mid-May easing of prohibitions on firing U.S.-provided munitions across the border from inside Ukraine toward incoming Russian air- and ground-launched strikes, Kirby said that “they are allowed to use U.S.-provided material to defend themselves against Russian aggression.”

“We are still examining that policy,” he said of the remaining restrictions.

U.S. officials previously said the revised policy narrowly focused on using weapons like howitzers and rocket artillery to fire from Ukraine into Russia. The change specifically left in place restrictions on using long-range munitions, known as ATACMS, and did not address bringing weapons and vehicles overland onto Russian soil. Yet Ukrainian forces, according to analysts and soldiers on the ground, are already using U.S. equipment in their Kursk offensive, including Stryker personnel carriers, Humvees and armored MRAP vehicles.

Reaffirming the policy in recent days, U.S. officials have not publicly said it is being violated in Kursk.

Late Thursday, Ukrainian Air Force Commander Lt. Gen. Mykola Oleschuk posted a video on Telegram purporting to show a Russian base in Kursk being hit by what he said were air-launched glide bombs provided by the United States. “This is what the Air Force airstrike with high-precision American GBU-39 bombs looks like on a platoon base in the Kursk region,” Oleschuk wrote, adding that the strike hit a Russian command post, equipment, weapons and “up to 40 Russian servicemen.”

U.S. administrations have at times defined American strikes in places such as Iraq and Yemen as “preemptive” defense rather than offense. As the Biden administration grapples with that question in Ukraine, President Volodymyr Zelenskyy has called for the lifting of all U.S. “red lines.”

European Union foreign policy head Josep Borrell this week also called for “lifting restrictions on the use of capabilities versus the Russian military involved in aggression against Ukraine … by ending Russia’s sanctuary for its attacks and bombardments of Ukrainian cities and infrastructure.” E.U. foreign and defense ministers, he said, would discuss how to “move forward in our support” of Kyiv at discussions in Brussels next week.

Russia has publicly charged, and the administration has sharply denied, U.S. complicity in the offensive. This week, the Russian Foreign Ministry summoned Stephanie Holmes, the deputy chief of mission at the U.S. Embassy in Moscow, to protest what officials said were American journalists “illegally” entering Russia, accompanied by Ukrainian troops, to report on the incursion. Russian officials also claimed, without evidence, the presence of U.S. “mercenaries” among Ukraine’s forces in Kursk.

U.S. officials have said they have not provided intelligence to aid the Kursk operation. “I don’t foresee the United States helping or providing assistance in intel sharing that would enable the further taking of sovereign Russian territory,” a second U.S. official said.

Zelenskyy has already claimed some successes from the surprise offensive, including creating a buffer zone around Ukraine’s northeastern Sumy region, which had been taking heavy bombardment from Russian forces. Ukrainian forces have also captured hundreds of Russian prisoners of war — an action Zelenskyy has referred to as replenishing the “exchange fund” Kyiv will use to gain the return of its own soldiers held by Russia.

Ukrainian officials have said the Russian land grab will give them a powerful bargaining chip in any future peace talks.

The Kursk offensive has been a public relations win for Ukraine’s commanders, and for a country unified but exhausted by years of war. Facing a lack of military-age conscripts, Kyiv has implemented a new mobilization campaign — drafting some 30,000 troops a month, according to analysts and Western officials. But extending the front into Kursk with a military that is already undermanned across the battlefield in Ukraine is a risk.

Ukraine’s military command had calculated that Russia would divert forces from elsewhere along the front in eastern Ukraine to defend Kursk, but so far Moscow has avoided pulling units out of the eastern Donetsk region.

Meanwhile, Russian forces have been closing in on the strategic eastern town of Pokrovsk, and some Ukrainian soldiers have said defending the area has gotten more difficult now that reserves and ammunition are being sent north to Kursk and civilian evacuations have begun.

But the United States is not offering advice, and Kyiv hasn’t asked for it, a U.S. official said. “They’re going to do what they’re going to do.”

Khurshudyan reported from Kyiv. Dan Lamothe and Missy Ryan contributed to this report.

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