U.S. cluster munitions have arrived in Ukraine, according to Joint Staff Director for Operations Lt. Gen. Douglas Sims.

Sims said that in contrast to Russia, Ukraine is aware of the possible danger to civilians, and does not intend to use them near population centers.

"I don't think that Ukrainians have any interest in using the cluster munitions anywhere near the civilian population, unlike the Russians," Sims told reporters.

-ABC News' Matt Seyler

Coming off a "very productive summit" with NATO allies, President Joe Biden offered a forceful dismissal of Vladimir Putin’s efforts to capture Ukraine during a joint press conference in Helsinki with Finnish President Sauli Niinisto.

"There is no possibility of him winning the war in Ukraine. He's already lost that war," Biden said.

Biden has made similar statements before about Putin’s chances of success, though it’s particularly notable coming off of his meeting with Ukrainian President Volodymyr Zelenskyy and his top military officials Wednesday.

Biden wouldn’t give a timeline for how long he thinks the war can continue, but he ruled out a yearslong offense.

"I don't think the war could go on for years for two reasons. No. 1, I do not think that Russia could maintain the war forever -- No. 1 in terms of their resources and capacity. No. 2, I think that there is going to be a circumstance where eventually, President Putin is going to decide it’s not in the interest of Russia economically, politically or otherwise to continue this war," Biden said.

"But I can't predict exactly how that happens," he continued. "My hope is and my expectation is you’ll see that Ukraine makes significant progress on their offensive and that it generates a negotiated settlement somewhere along the line."

-ABC News' Molly Nagle and Cheyenne Haslett

U.S. National Security Council spokesman John Kirby said Thursday that "it remains to be seen" whether Russia has recovered from last month's brief but chaotic mutiny and if it will have any notable effect on the fighting in Ukraine.

"We don't exactly know what transpired every minute of that event and we don't really know what kind of impact it's going to have on the war in Ukraine," Kirby told ABC News' George Stephanopoulos during an interview on "Good Morning America."

"As we speak, there hasn't really been that much of an effect on the fighting in Ukraine," he added. "The Russians are dug in. The Ukrainians are trying to claw back territory. We're still trying to help them win."

Ukrainian forces are in the midst of a counteroffensive, "all the way from the Donbas area down toward Zaporizhia to the south," according to Kirby.

"They're making halting progress, not as fast [or] as far as they'd like to go, but we're going to do everything we can to give them the tools and capabilities to succeed," he said. "It could be weeks, it could be months of hard fighting here as they try to claim back the rest of their country."

Russian Foreign Intelligence Director Sergey Naryshkin claims he had a phone conversation with CIA Director William Burns in late June, according to the Russian state media outlet TASS.

"The bulk of the conversation was focused on discussing Ukraine and events around it. We gave some thought to and deliberated on what should be done about Ukraine," Naryshkin claimed to the outlet.

The CIA declined to comment about the alleged call.

The alleged conversation lasted "about an hour," according to Naryshkin.

The Russian intel chief noted that arranging an in-person meeting between him and the CIA leader remained a possibility.

-ABC News' Anastasia Bagaeva

U.S. President Joe Biden will make a "memorable speech" before world leaders in Lithuania's capital on the final day of a high-stakes NATO summit, according to National Security Council Senior Director for Europe Amanda Sloat.

Biden's remarks on Wednesday afternoon will focus on similar themes to what he said during his speech in Poland in late February marking one year since Russia waged war on Ukraine.

"President Biden will talk about the strength of the NATO Alliance and how it remains a force for global security and stability, as it has for more than seven decades. He'll talk about how NATO is more vital to our shared future and that didn't happen by accident," Sloat told reporters during a press briefing in Vilnius on Wednesday morning.

"As the president has talked about before, Vladimir Putin thought he could break our resolve when he invaded Ukraine. But our NATO allies and our partners around the world responded by coming together to support the brave people of Ukraine as they defend their freedom, their independence and their democracy," she added.

Beyond addressing the strength of the NATO alliance and the importance of standing by Ukraine, Biden will also look to pitch cooperation like we've seen for Ukraine to tackle other major challenges facing the world, "including the climate crisis, emerging technologies, upholding the international rules of the road and expanding opportunities so we build an economy where no one gets left behind," according to Sloat.

-ABC News' Molly Nagle