Biden Suspects Russia Will Be in Ukraine for the 'Long Haul,' as Official Warns to Not Underestimate Putin

This photograph taken on September 11, 2022 shows a destroyed building in the city of Izium, Kramatorsk, eastern Ukraine, amid the Russian invasion of Ukraine. - Ukraine said on Sptember 11, 2022, that its forces were pushing back Russia's military from strategic holdouts in the east of the country after Moscow announced a retreat from Kyiv's sweeping counter-offensive. (Photo by Juan BARRETO / AFP) (Photo by JUAN BARRETO/AFP via Getty Images)
This photograph taken on September 11, 2022 shows a destroyed building in the city of Izium, Kramatorsk, eastern Ukraine, amid the Russian invasion of Ukraine. - Ukraine said on Sptember 11, 2022, that its forces were pushing back Russia's military from strategic holdouts in the east of the country after Moscow announced a retreat from Kyiv's sweeping counter-offensive. (Photo by Juan BARRETO / AFP) (Photo by JUAN BARRETO/AFP via Getty Images)

JUAN BARRETO/AFP via Getty Izium, Ukraine

President Joe Biden isn't ready to speculate on the state of the war in Ukraine.

Asked Tuesday evening if the recent liberation of key Ukrainian cities marks a turning point in Russia's invasion, Biden said the question is "unanswerable right now."

"It's clear the Ukrainians have made significant progress," he said, "but I think it's going to be a long haul."

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For months, reports have claimed that Russian soldiers are suffering from exhaustion and a lack of resources. But U.S. officials are cautious about applying anecdotes to the larger picture, noting that war is unpredictable and only Vladimir Putin and Volodymyr Zelenskyy can speak to the positions their nations are in.

"Certainly in the north [of Ukraine], we have seen Russians evacuate, withdraw, or retreat from their defensive positions, particularly there in and around the Kharkiv Oblast," John Kirby, strategic communications coordinator for the National Security Council, told reporters Tuesday.

"They have left fighting positions. They have left supplies. They're calling it a repositioning, but it's certainly — they have withdrawn in the face of Ukrainian Armed Forces that are clearly on the offense."

Acknowledging the shift in momentum on Ukrainians' part, Kirby said it's up to Zelenskyy to "determine and decide whether he feels, militarily, they've reached a turning point."

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But despite the self-made challenges Russian soldiers have faced in terms of command and control, logistics and sustainment, and unit cohesion, Kirby reminded Americans that Russia is still viewed as an "acute threat" by the Department of Defense — and that their shortcomings on the battlefield do not alter their status as a world superpower.

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"They clearly still have a military capable of inflicting great damage and casualties. And we've seen that, sadly, to some effect in Ukraine," he said. "It's still a very large and very powerful military, and Mr. Putin still has an awful lot of military capacity left at his disposal — not just to be used in Ukraine, but potentially elsewhere."

For now, the U.S. government is standing at a distance and supporting Ukraine where appropriate. "We're in lockstep with the Ukrainians, talking to them every day," Kirby said. "What we're going to do is continue to support them as best we can."

The Russian attack on Ukraine is an evolving story, with information changing quickly. Follow PEOPLE's complete coverage of the war here, including stories from citizens on the ground and ways to help.