The U.S. Department of Defense announced a new $325 million military aid package for Ukraine, including more rockets and artillery rounds, in addition to other equipment.

Defense Secretary Lloyd Austin and Gen. Mark Milley are in Europe to attend another meeting of the 50-plus countries providing military assistance to Ukraine that begins later this week in Ramstein, Germany.

"The United States will continue to work with its Allies and partners to provide Ukraine with capabilities to meet its immediate battlefield needs and longer-term security assistance requirements," the Pentagon said in a statement.

-ABC News' Luis Martinez

The German government announced Tuesday that it delivered a Patriot missile defense system and missiles to Ukraine this week.

The country also sent 16 Zetros trucks, bringing its total to 76, and two border patrol vehicles, bringing its total to 124, the government said.

-ABC News' Will Gretsky

Russia's security services have arrested an anti-Kremlin political commentator who the jailed Wall Street Journal reporter Evan Gershkovich met with shortly before his own arrest.

Yaroslav Shirshikov has said he spent two days showing Gershkovich around the city of Yekaterinburg during a reporting trip there a couple of weeks before Russia seized Gershovich.

Shirshikov said he had been due to meet with Gershkovich again the week the reporter was arrested in the city.

This morning, local media published video showing masked security officers detaining Shirshikov in his apartment and searching it.

A local news outlet cited a security services representative saying Shirshikov may have been arrested for posting comments cheering the assassinations of two ultra-nationalist pro-war figures, Daria Dugina and the blogger Vladen Tatarsky.

The site UralLive quoted a law enforcement source that Shirshikov was detained on a charge of “justifying terrorism”, which carries a maximum sentence of 7 years prison. It linked the charge to a social media post in which Shirshikov wrote he wasn’t sad over the death of Tatarsky, who was killed in a bomb attack in St. Petersburg this month.

Shirshikov spoke to several international media outlets including ABC following Gershkovich's arrest. He said that Gershkovich had acted entirely as a professional journalist in Yekaterinburg, conducting interviews openly and doing usual reporting.

Shirshikov is a critic of the Russian government and has spoken publicly about his opposition to the war in Ukraine.

-ABC News' Patrick Reevell

Russian President Vladimir Putin made a trip to Kherson and Luhansk, visiting a military headquarters in occupied territory in Ukraine.

Putin arrived via helicopter at the headquarters of an army group in occupied Kherson, according to video released on Tuesday by the Kremlin.

In brief remarks after he arrived, Putin said he didn't want to distract troops from their mission, saying his tour of the installation would be in a "businesslike manner, briefly, but concretely," according to Interfax, a Russian state-affiliated news wire.

"It is important for me to hear your opinion on how the situation is developing, to listen to you, to exchange information," he said, according to Interfax.

-ABC News' Joe Simonetti

One year ago, with Ukraine's borders surrounded by what seemed to be a superior military force, many U.S. officials and analysts predicted a swift Russian blitz to Kyiv.

But after Russian President Vladimir Putin sent his more than 150,000 arrayed troops across the border, it soon became clear that a dual reassessment was in order: The Russian invaders were less potent than advertised, and the Ukrainians were unexpectedly stubborn and wily in the defense.

Some of the Russian troops weren’t even aware they were on a combat mission until Ukrainian bullets came cracking past them, according to U.S. officials. Meanwhile, Ukrainian forces stalled a massive Russian supply convoy through direct attacks and by destroying a key bridge. Only one week into the invasion, Putin's men were plagued with food and fuel shortages, morale running similarly low.

Kyiv stood.

"Putin assumed that Ukraine was an easy target, Putin assumed that Kyiv would easily fall, and Putin assumed that the world would stand by," U.S. Secretary of Defense Lloyd Austin said during a speech in Brussels last week. "But the Kremlin was wrong on every count."

Ukrainian forces were armed with more than grit.

They also had years of U.S. and NATO military training, plus American-made weapons, like anti-armor Javelins and anti-aircraft Stinger missiles. These made Russian vehicles vulnerable to ambush, and left Russian helicopter and jet pilots wary of flying over Ukrainian positions. Indeed, many airmen did not return from their sorties.

Despite astonishing losses of soldiers and vehicles, Putin has shown no inclination to end the conflict anytime soon. And despite its tenacity, Ukraine has also taken significant casualties, and is not able to produce enough of its own weapons and ammunition to keep up the fight.

Ukraine, after thwarting the advance on its capital, and later routing Russian forces from Kharkiv, now largely faces a battle of supply.

"When this war began, Russia had a larger population, a much bigger defense budget, a bigger military, bigger industrial base. So, this became an industrial war and a war of industrial bases," said Seth Jones, director of the International Security Program at the Center for Strategic and International Studies. "This is why Western industrial support has been so critical."

A key question now is, despite massive military aid packages and a promise to send even more, could the U.S. strategy ultimately result, not in a Ukrainian victory, but a stalemate in a years-long war of attrition?

-ABC News' Matt Seyler