Poland says missile strike on its territory was 'isolated incident,' but 'Alliance is on standby'

The president of Poland said his authorities doesn't yet conclusively cognize who fired a rocket that struck Polish territory precocious Tuesday, sidesplitting 2 civilians.

The explosion, which took spot astir 15 miles (24 km) from the Ukrainian border, came arsenic Russia was launching a monolithic question of missiles astatine Ukrainian cities and vigor facilities conscionable earlier dusk section time.

President Andrzej Duda said the projectile was "Russian-made" and variously referred to it arsenic either a rocket oregon a rocket.

"What happened was an isolated incident," said Duda, who added that an probe is underway. "There is nary denotation that much volition instrumentality place"

Poland is simply a subordinate of NATO. The improvement acceptable disconnected a concatenation of diplomatic enactment among members of the confederation and Ukraine, which is not a NATO subordinate but which gets monolithic subject assistance from the alliance.

U.S. President Joe Biden spoke with Duda and "offered afloat U.S. enactment for an assistance with Poland's investigation," the White House said. "President Biden reaffirmed the United States' ironclad committedness to NATO."

Warsaw was besides successful connection with NATO Secretary General Jens Stoltenberg, U.K. Prime Minister Rishi Sunak, French President Emmanuel Macron and German Chancellor Olaf Scholz.

"The North Atlantic Alliance is connected standby," Duda said. "We person strengthened the readiness of the Polish equipped forces, including the aerial defense. Our planes volition beryllium supported by allied planes. We enactment calmly and prudently."

Moscow offered nary comment. Russia's Ministry of Defense did not instantly respond to a CNBC petition for comment.

Duda said Ukrainian President Volodomyr Zelenskyy had assured Warsaw that "it was a rocket launched from the territory of the Russian Federation."

Poland's Minister of Foreign Affairs Zbigniew Rau summoned the ambassador of the Russian Federation "and demanded contiguous elaborate explanations," the Polish ministry said.

Biden, Macron, China's Xi Jinping and different planetary leaders are gathered successful Bali, Indonesia, for the Group of 20 summit. G-20 nations are expected to contented a communique condemning Russia's penetration of Ukraine, according to a draught mentation of the papers seen by CNBC.

— NBC News' Ewa Galica and CNBC's Silvia Amaro contributed to this report.

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