Ukraine has asked the Biden administration to provide more intelligence on the position of Russian forces and military targets inside Russia as Ukrainian troops struggle to hold ground in the war, according to U.S. and Ukrainian officials.
A group of Ukrainian Parliament members also met with members of Congress in Washington to press for the United States to allow Kyiv to use American weapons in Russia.
Ukraine’s requests have become more urgent in recent weeks as Russia has taken advantage of delays in shipments of American weapons and intensified military operations in the Kharkiv region of northeastern Ukraine.
But White House officials said the administration’s longstanding policy remained unchanged: The United States is not encouraging or enabling attacks inside Russia. American officials, seeking to avoid escalating the war, have insisted they do not want U.S. weapons used in cross-border attacks or their intelligence reports used to target sites in Russia.
The latest request came in recent days, officials said, and administration officials have begun to review it. Similar appeals have been turned down in the past.
The United States provides some intelligence to Ukraine on Russian forces in Russia, for example, on troops that are massing for potential attacks. Ukraine also has access to commercial satellite imagery that allows it to see Russian activity at major military bases.
But Ukrainian officials say they need to increase the number and effectiveness of their cross-border attacks to press Moscow to end the war, according to current and former Ukrainian officials. To do that, those officials say they want more real-time intelligence and more information from allies on what U.S. and European officials think are the most critical targets.
Gen. Charles Q. Brown Jr., the chairman of the Joint Chiefs of Staff, said that the Ukrainians had been “asking us for help to be able to strike into Russia” but that the request was broad and not “specific to a weapons system.”
At the moment, “we don’t help them with any of their stuff they do into Russia,” he told reporters on Thursday on his flight to Brussels for NATO meetings.
A former Ukrainian official said American and allied intelligence on Russian military assets across the border would allow Ukraine to more accurately plan routes for its drones and guided missiles. Those weapons must fly low to avoid radar, requiring detailed terrain mapping.
And while some commercial imagery helps the Ukrainians locate Russia’s mobile air defenses, American intelligence would provide better and faster information.
There are signs that Ukraine’s cross-border strategy is becoming more effective, and allied officials say an expanded campaign, particularly one targeting Russia’s defense industry and manufacturing plants, would be critical to changing the trajectory of the war.
On Friday, President Vladimir V. Putin of Russia said his troops were moving into the Kharkiv region to carve out a buffer zone that would make it more difficult for Ukrainian forces to strike the Russian border city of Belgorod.
American officials say those strikes have been a major irritant for the Kremlin. General Brown said Russia did not appear to have enough forces or supplies to take Kharkiv.
In the face of Russia’s incremental gains, and Ukraine’s critical shortage of troops, NATO allies are considering starting training missions inside Ukraine. Much military training is done at the unit level, and Ukraine has struggled to create a national program.
But American officials have cautioned allied governments about sending troops to Ukraine, worried that if Russia targeted them or they were killed in a strike, the alliance could quickly be drawn into a wider war.
Similar to the training missions, allied governments are considering loosening their restrictions on Ukraine’s cross-border actions, including by providing more intelligence on potential targets and allowing their weapons to be used inside Russia, Western officials said.
David Cameron, the British foreign secretary, said during a visit to Kyiv this month that Ukraine had “the right” to use weapons provided by London to strike targets inside Russia.
“Just as Russia is striking inside Ukraine, you can quite understand why Ukraine feels the need to make sure it’s defending itself,” Mr. Cameron told Reuters.
Russia responded to those comments with a threat to strike British military facilities and equipment in Ukraine “and beyond.” The Kremlin also summoned the British ambassador in Moscow to deliver a message of protest.
The United States has said it was up to Ukraine to decide whether to strike into Russia.
“We have not encouraged or enabled strikes outside of Ukraine, but ultimately Ukraine needs to make decisions for itself on how it conducts this war,” Secretary of State Antony J. Blinken said on Wednesday. “We will continue to back Ukraine with the equipment it needs to win.”
Elbridge Colby, a critic of the Biden administration’s policies on Ukraine, said the tensions between Britain and Russia over Mr. Cameron’s remarks showed the dangers of insufficiently considered escalation.
“These Russian counterthreats are very concrete and relatively proportional,” said Mr. Colby, who was a Pentagon official during the Trump administration. “And that’s the thing that worries me.”
Providing intelligence to the Russians would be a significant erosion of the guardrails the Biden administration has put in place to prevent the conflict from widening beyond the borders of Ukraine, he added.
“Like in the early years in Vietnam, we are step by step moving toward the erosion of the boundaries that we have set for ourselves,” Mr. Colby said. “We’ve been in this for two and a half years. We’re in a war of attrition with Russia and we’re steadily escalating. Is that where we want to be?”