U.S. President Joe Biden on November 17 disputed Ukrainian President Volodymyr Zelenskiy's comment that missiles that landed in Poland were not of Ukrainian origin.
"That's not the evidence," Biden told reporters at the White House upon returning from a trip to Asia.
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Biden's statement followed comments by NATO chief and Poland that the November 15 blast in Polish territory was likely caused by a Ukrainian air-defense missile.
"From the information that we and our allies have, it was an S-300 rocket made in the Soviet Union, an old rocket, and there is no evidence that it was launched by the Russian side," Polish President Andrzej Duda said on November 16. "It is highly probable that it was fired by Ukrainian antiaircraft defense."
NATO Secretary-General Jens Stoltenberg also said it was likely to have been a Ukrainian air-defense missile fired to shoot down incoming missiles on November 15 during what Kyiv said was Russia's most intensive wave of missile attacks on cities across Ukraine since the start of the war in February.
Nevertheless, Stoltenberg said Russia, not Ukraine, was still to blame for starting the war with its February invasion.
"This is not Ukraine's fault. Russia bears ultimate responsibility as it continues its illegal war against Ukraine," NATO Secretary-General Jens Stoltenberg told reporters in Brussels.
Speaking on November 17, U.S. Secretary of State Antony Blinken also said Russia bore responsibility for the blast in Poland.
Addressing reporters at an Asia-Pacific summit in Bangkok, Blinken said he had spoken again with his Ukrainian counterpart on the probe but added: "Whatever its final conclusion, we already know the party ultimately responsible for this tragic incident: Russia."
"I have no doubt that it was not our missile," Ukrainian President Volodymyr Zelenskiy was quoted as saying on November 16. "I believe that this was a Russian missile, based on our military reports," he said on Ukrainian television.
SEE ALSO: The Drones Of The Ukraine WarMeanwhile, Ukraine's General Staff said on November 17 that Ukrainian forces had repelled attacks on the Donetsk towns of Avdiyivka and Bilohorivka.
Meanwhile, missile strikes were reported accross Ukraine by officials.
Prime Minister Denys Shmyhal said new Russian missile strikes on November 17 targeted gas production facilities and a missile plant, the Interfax Ukraine news agency reported.
"Missiles are flying over Kyiv right now. Now they are bombing our gas production [facilities]; they are bombing our enterprises in Dnipro and Yuzhmash [missile factory]," Shmyhal was quoted as saying. Russia has increasingly resorted in recent weeks to aerial attacks aimed at energy infrastructure in parts of Ukraine it doesn't hold.
Odesa regional Governor Maksym Marchenko said on Telegram that a Russian missile strike hit the southern Odesa region for the first time in weeks.
Marchenko said an infrastructure target was hit while warning about the threat of a "massive missile barrage on the entire territory of Ukraine." He called on residents in the region to remain in bomb shelters.
Separately, UN Secretary-General António Guterres on November 17 welcomed an extension of a four-month-old deal to ensure the safe delivery of export of grain, foodstuffs, and fertilizers from Ukraine through the Black Sea just days before it was set to expire.
Guterres says the United Nations is also "fully committed" to removing obstacles that have impeded the export of food and fertilizer from Russia, which is one of two agreements struck between the two countries and Turkey in July. The deals signed in Istanbul are aimed to help bring down prices of food and fertilizer and avoid a global food crisis.
In Photos: Days after their liberation by Ukrainian forces, residents of the southern port city of Kherson are facing shortages of water and electricity as authorities step up efforts to deliver humanitarian aid.
Hard Life In Ukraine's Kherson After The Liberation
In another development, Ukrainian Interior Minister Denys Monastyrskiy said on November 17 that investigators in the recently liberated southern Kherson region have uncovered 63 bodies with signs of torture after Russian forces left the area.
"Now, 63 bodies have been discovered in the Kherson region, but we must understand that the search has only just started so many more dungeons and burial places will be uncovered," the press service of the Interior Ministry quoted Monastyrskiy as saying.
Monastyrskiy said law enforcement bodies had uncovered 436 instances of war crimes during Russia's occupation. Eleven places of detention had been discovered, including four where torture had been practiced.
Ukrainian forces entered the strategic southern city of Kherson on November 11 following the retreat of Russian forces.
The White House hailed Russia's withdrawal from Kherson as an "extraordinary victory" for Ukraine.