Ukrainian President Volodymyr Zelenskiy says his forces have made "rapid and powerful" gains in southern Ukraine and recaptured "dozens" of villages from Russia this week.
"The Ukrainian Army is quite rapidly and powerfully advancing in the south," Zelenskiy said in his nightly video address on October 4.
He said some of the territory was taken back in the regions of Kherson, Luhansk, and Donetsk -- three of four regions of Ukraine where referendums that Kyiv and the West denounced as a "sham" were held last month on joining Russia.
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Zelenskiy cited eight settlements in the southern Kherson region where Moscow's forces had retreated in the face of a sweeping Ukrainian counteroffensive. And he said the eight settlements were "far from the full list."
Zelenskiy made the claim as maps revealed by Moscow on October 4 showed that Russian troops had left many areas in Kherson, including along the west bank of the Dnieper River.
The Moscow-appointed deputy head of the Kherson region told residents there was no reason to panic. "Our artillery and fighter jets are hitting enemy forces that enter the sovereign territory of Russia," Kirill Stremousov said.
Neither side's claims could be independently verified.
In the northeastern Kharkiv region, the mapping indicated that Russian forces had almost entirely abandoned the east bank of the Oskil River.
But Russian troops again struck the energy infrastructure of Kharkiv later on October 4, Mayor Ihor Terekhov said. Russian forces are intentionally destroying transformers in order to cut off electricity and prevent people from having a normal life, he said.
Earlier on October 4. U.S. President Joe Biden told Zelenskiy in a phone call that the United States will provide Kyiv with $625 million in new security assistance.
The assistance will include more high-mobility artillery rocket systems (HIMARS), ammunition, and armored vehicles, the White House said in a statement.
Biden "pledged to continue supporting Ukraine as it defends itself from Russian aggression for as long as it takes," the statement said.
The U.S. president also affirmed that the United States was prepared "to impose severe costs on any individual, entity, or country that provides support to Russia's purported annexation."
The statement noted that Biden was joined on the call by Vice President Kamala Harris.
U.S. Secretary of State Antony Blinken said in a statement that the $625 million in aid will be the 22nd drawdown of U.S. arms and equipment for Ukraine since August 2021 from Department of Defense inventories and will bring the total U.S. military assistance for Ukraine to more than $17.5 billion since the beginning of the Biden administration.
"The capabilities we are delivering are carefully calibrated to make the most difference on the battlefield and strengthen Ukraine's hand at the negotiating table when the time is right," Blinken said.
Zelenskiy thanked Biden and the American people for "continued defense and financial support," and said the discussion included "additional sanctions [and] the situation on the battlefield," according to Zelenskiy on Facebook.
"I enjoyed hearing President Biden say that our military inspires the world, our people inspire the world," he added.
Zelenskiy earlier on October 4 signed a decree that officially declares any negotiations between Kyiv and Russian President Vladimir Putin "impossible."
The decree implemented a decision by Ukraine's National Security and Defense Council and formalized comments made by Zelenskiy on September 30 after Putin proclaimed four regions of Ukraine partially occupied by Moscow as being a part of Russia, in what Kyiv and the West said was an illegitimate farce.
"He (Putin) does not know what dignity and honesty are. Therefore, we are ready for a dialogue with Russia, but with another president of Russia," Zelenskiy said on September 30.
The decree also states that Ukraine will use military means to bring the territories occupied by Russia back under its control.
The White House statement reiterated Washington's position that it will never recognize Russian annexation of Ukrainian territory.
In Moscow, the upper chamber of Russia's parliament, the Federation Council, on October 4 ratified agreements incorporating four regions into Russia, a further step toward what the West has said is an illegal annexation of the territories.
All of the 153 deputies who were present at the session voted for the annexation of parts of Ukraine's Zaporizhzhya, Kherson, Donetsk, and Luhansk regions.
A day earlier, parliament's lower chamber, the State Duma, approved the move. The final step in the process is the signing of the documents into law by Putin.