U.S. President Joe Biden and other G-7 leaders are set to unveil future support for Ukraine on Wednesday after the conclusion of a high-stakes NATO summit in Lithuana's capital.

"President Biden and G-7 leaders will make a major announcement alongside President Zelenskyy this afternoon outlining our long-term commitments to support the people of Ukraine," U.S. National Security Council Senior Director for Europe Amanda Sloat said during a press briefing in Vilnius on Wednesday morning. "The United States, along with G-7 leaders, will announce our intent to help Ukraine build a military that can defend itself and deter a future attack."

"The launch of this process today will start a series of bilateral negotiations with Ukraine on the reaching of bilateral security commitments to help make this a reality," she added. "In particular, this process will ensure that the military assistance we provide Ukraine to defend itself against Russian aggression continues to be part of a long-term investment in Ukraine’s future force."

That investment will include making sure "Ukraine has a sustainable fighting force capable of defending Ukraine now and deterring Russian aggression in the future, a strong and stable economy, and the help Ukraine needs to advance the reform agenda to support the good governance necessary to advance Ukraine's Euro-Atlantic aspirations, which Ukraine recommits itself to as part of this declaration," according to Sloan.

"Taken together, we believe the declaration we will announce today seeks to ensure Ukraine's future as a free, independent, democratic, and sovereign nation," she told reporters. "This multilateral declaration will send a significant signal to Russia that time is not on its side."

-ABC News' Molly Nagle

Russian Defense Minister Sergei Shoigu made his first public comments since last month’s failed rebellion led by Wagner Group boss Yevgeny Prigozhin and claimed that Russian President Vladimir Putin is actively engaged with his commanders
Shoigu said that Putin listens to "very detailed reports" twice a day and "all commanders on all levels understand and feel all the weight of responsibility that was placed on them."

"They carry out their responsibilities with great pride," he said.

Shoigu claimed that Ukraine hasn't achieved any of its goals in its counteroffensive. The defense minster added that Russia may be using cluster munitions following the announcement that Ukraine will be receiving similar weapons from the U.S.

"If the United States supplies cluster munitions to Ukraine, the Russian Armed Forces will be forced to use similar weapons against the Armed Forces of Ukraine as a response," he said.

-ABC News' Natalia Shumskaia, Ellie Kaufman and Will Gretsky

Russia will take “early and adequate measures” in connection with Sweden and Finland joining NATO, Russian Foreign Minister Sergei Lavrov said Tuesday after the start of the NATO summit in Vilnius, Lithuania.

Lavrov told reporters that he is convinced that "the speed with which this happened, of course, forces us to look for the reason in the complete subordinate position in which these countries have placed the United States and the rest of the collective West,” according to the Russian news agency Interfax.

-ABC News' Natalia Shumskaia and Ellie Kaufman

Ukraine will get an invitation to join NATO when all the allies agree and all the conditions are met, Secretary General Jens Stoltenberg said during a press conference from the NATO summit in Vilinus, Lithuania, on Tuesday.

NATO agreed to remove the required membership action plan, he added, which makes the process take only one step instead of two.

A NATO-Ukraine Council will also be launched, Stoltenberg announced. The first session is planned for Wednesday with participation from Ukrainian President Volodymyr Zelenskyy, he said.

Zelenskyy had criticized the process for joining NATO ahead of his trip to Lithuania, saying, "It’s unprecedented and absurd when timeframe is not set neither for the invitation nor for Ukraine's membership."

-ABC News' Fidel Pavlenko

Ukrainian troops have reportedly seized a small village on the Russian-occupied eastern bank of Dneipr after crossing the river from the liberated city of Kherson, according to Russian accounts on Tuesday.

A small Ukrainian force has managed to dig in to the village of Dachi after making a landing there a few days ago and are trying to expand the beachhead. Ukrainian troops in small boats crossed the river and landed at the base of the ruined Antonivskiy Bridge, which they destroyed last year.

Russian military bloggers reported very heavy fighting on Tuesday, saying Russian airborne units have been trying unsuccessfully to dislodge the Ukrainians for the past four days. Russian aviation and heavy artillery have been firing on the Ukrainian position.

So far, the Russian side claims some 70 Ukrainian soldiers are dug in, covered by intense artillery fire from across the river. The Russian accounts say Ukraine is trying to move reinforcements across. Video released by Ukraine also shows a Russian APC being destroyed in the village of Oleshkjy, further south, indicating the bank south of Kherson is now contested.

Ukrainian troops have also managed to advance and liberate Rivnopil, a village on the Zaporozhzhia front, breaking through after more than two weeks of fighting. It's notable because the Russians had been fighting hard to hold it.

Taken together the advance there, the landing in Kherson and advances near Bakhmut are small signs the Ukrainian counteroffensive may be starting to pick up steam and the Russians are coming under growing pressure.

-ABC News' Patrick Reevell