US president Joe Biden, when prodded on whether the missile that landed in Poland was Ukrainian, said that Zelensky’s comments did not amount to evidence as NATO and Poland concluded that the missile was probably a stray fired by Ukraine‘s air defences.

NATO ambassadors held emergency talks on Wednesday to respond to Tuesday’s blast that killed two people at a grain facility in Poland near the Ukrainian border, the war‘s first deadly extension into the territory of the Western alliance.

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“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.

It is highly probable that it was fired by Ukrainian anti-aircraft defence, the president added.

NATO’s chief said that Russia, not Ukraine, was still to blame for starting the war with its February invasion and launching scores of missiles that triggered Ukrainian defences.

“This is not Ukraine‘s fault. Russia bears ultimate responsibility as it continues its illegal war against Ukraine,” NATO secretary-general Jens Stoltenberg said adding that it was likely to have been a Ukrainian air defence missile.

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Earlier, US President Joe Biden had said the trajectories suggested the missile was unlikely to have been unleashed from Russia as Moscow continued to deny responsibility.

Ukrainian president Volodymyr Zelenskiy has although said. “I have no doubt that it was not our missile” adding that he based his conclusion on reports from Ukraine‘s military which he “cannot but trust”, without giving any evidence for his position.

Zelensky urged that Ukraine be included in the investigation of the explosion site in Poland in order to determine the facts.