Russia-Ukraine updates: 2 US veterans who joined Ukrainian forces missing

Sen. Rand Paul, R-Ky., had a heated back and forth with Secretary of State Antony Blinken on Capitol Hill over the war in Ukraine.

Paul pushed Blinken on support for Ukraine’s possible membership in NATO and what he called "the reasons" for the Russian invasion.

"I'm saying that the countries that have been attacked, Georgia and Ukraine, were part of the Soviet Union since 1920s,” he said.

“That does not give Russia the right to attack them,” Blinken said, explaining that the Kremlin’s security concerns about Ukraine joining NATO were adequately weighed and attempts at diplomacy were made.

"It is abundantly clear, in President Putin's own words, that this was never about Ukraine, being potentially part of NATO, and it was always about his belief that Ukraine does not deserve to be a sovereign independent country that it must be reassumed into Russia in one form or another," Blinken said.

Paul interjected during Blinken’s answer, denying he was making the argument that Russia’s actions were justified. The senator then asked Blinken about talks between Russia and Ukraine and the potential outcomes.

“Would the U.S. would President Biden be open to accepting Ukraine as an unaligned neutral nation?” Paul asked.

“We're not going to be more Ukrainian than the Ukrainians. These are decisions for them to make," Blinken said.

-ABC News' Shannon Crawford and Connor Finnegan

The United States returned diplomats to Ukraine for the first time since the beginning of the Russian invasion with a team making a day trip across the border from Poland to meet Ukrainian Ministry of Foreign Affairs officials, the State Department confirmed on Tuesday.

"The deputy chief of mission and members of the embassy team traveled to Lviv, Ukraine, today, where they were able to continue our close collaboration with key Ukrainian partners," said State Department spokesperson Ned Price.

Price called the move a "first step" toward eventually reopening the U.S. Embassy in Kyiv.

"Today's travel was a first step ahead of more regular travel in the immediate future. And as we've said, we're accelerating preparations to resume Embassy Kyiv operations just as soon as possible," Price said. "We are constantly assessing and evaluating and reassessing the security situation with a view toward resuming those embassy operations as soon as possible."

-ABC News' Conor Finnigan

Germany plans to supply Ukraine with "Gepard" anti-aircraft tanks, the German Minister of Defense announced Tuesday on Twitter.

"We made our decisions in coordination with our allies," German Defense Minister Christine Lambrecht said earlier Tuesday during a news conference at a meeting of NATO countries hosted by the United States at Ramstein Air Base. "That is, once it was clear others will deliver certain systems, we support them in that. We deliver as well. That is our way -- Germany is not doing it alone. And if Ukraine now urgently needs such air defense systems, then we are also prepared to support them."

Lambrecht said Tuesday's gathering of NATO countries to discuss strengthening Ukraine's military both in the short and long terms was a "starting point."

"The best security strategy for Ukraine is well-trained and equipped armed forces," Lambrecht said, "Germany has been providing a very high level of support in a variety of ways since the war began."

The move from Germany comes just days after Ukrainian Deputy Prime Minister Iryna Vereshchuk told ABC News that she was disappointed in Germany for seemingly dragging its feet on sending heavy artillery, including tanks, to Ukraine and said it appeared German leaders are attempting to placate Putin.

“They don’t understand. There is no way to pacify Putin," Vereshchuk said. "It would be a huge problem for NATO if Russia has dominance over the Black Sea.”

Speaking publicly about his visit to Ukraine for the first time since returning home, U.S. Secretary of State Antony Blinken declared to the Senate Foreign Relations Committee that “the Ukrainians have won the battle for Kyiv.”

Blinken, who visited Ukraine over the weekend with U.S. Defense Secretary Lloyd Austin, emphasized the need for additional aid to help Ukrainians weather the ongoing war as it enters its next phase.

“As we took the train across the border and rode westward into Ukraine, we saw mile after mile of Ukrainian countryside, territory that just a couple of months ago, the Russian government thought that it could seize in a matter of weeks. Today -- firmly Ukraine's," Blinken told the committee.

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Secretary Blinken testifies after trip to UkraineSecretary of State Antony Blinken testifies about the latest U.S. assessment of the war in Ukraine before the Senate Foreign Relations Committee.

ABCNews.com

Blinken said that while in Kyiv, he saw the signs of "a vibrant city coming back to life" with people eating outside, sitting on benches and strolling the streets.

“For all the suffering that they've endured, for all the carnage that Russia's brutal invasion continues to inflict, Ukraine was and will continue to be a free and independent country," he said.

Blinken said the United States has played a vital part in helping Ukrainian forces mount an effective resistance against Russia.

“I have to tell you, I felt some pride in what the United States has done to support the Ukrainian government and its people and an even firmer conviction that we must not let up," Blinken said. "Moscow's war of aggression against Ukraine has underscored the power and purpose of American diplomacy."

He added, "We have to continue to drive that diplomacy forward to seize what I believe are strategic opportunities, as well as address risks presented by Russia's overreach as countries are reconsidering their policies, their priorities, their relationships."

-ABC News' Shannon Crawford and Conor Finnegan