Ukrainian President Volodymyr Zelenskyy said Russia needs to "feel what it has done" after its attacks on his country, reports the BBC.

"Russia brought the war to our land and should feel what it has done," Zelenskyy said Thursday, three days after Ukraine fought back against attacks by Russia, launching an incursion on Russia's Kursk region.

"Ukrainians know how to achieve their goals. And we did not choose to achieve our goals in the war," he said.

Russian President Vladimir Putin called Ukraine's move to send troops into Russian territory, including tanks and armored vehicles, "a major provocation."

Zelenskyy said it's clear "the Ukrainian army knows how to surprise [and] achieve results," while Russia's defense ministry said it's firing back with "airstrikes, rockets, and artillery fire" on armed Ukrainian units.

Ukrainian Member of Parliament Oleksiy Honcharenko said the army now controls the Sudzha gas hub — an artery responsible for transporting natural gas from Russia to the EU through Ukraine.

The hub is the only way for Russian gas to reach the EU. While gas was still reportedly being transported from the hub as of Thursday, Russia's National Guard said it had reinforced security in the region.

White House press secretary Karine Jean-Pierre said the United States was in conversation with Ukraine to better understand the goal of the incursion.

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