A man suspected of aiding a plot by Russian intelligence services to assassinate Ukrainian President Volodymyr Zelenskyy has been arrested in Poland, Polish and Ukrainian prosecutors said Thursday.

The Polish national, named only as Pawel K., is suspected of supplying information to Russian military intelligence and "helping the Russian special forces to plan a possible assassination attempt" against Zelenskyy, said a statement from Polish prosecutors.

It said the suspect had stated he was "ready to act on behalf of the military intelligence services of the Russian Federation and established contact with Russian citizens directly involved in the war in Ukraine."

Ukrainian prosecutors had informed Poland about the activities, which had enabled them to gather "essential evidence" against the suspect, the statement added.

Ukraine's chief prosecutor Andriy Kostin said the suspect had been tasked with "gathering and transmitting to the aggressor state information about security at Rzeszow-Jasionka airport" in southeastern Poland.

Zelenskyy frequently passes through the airport on his trips abroad. It is also used by foreign officials and aid convoys heading to Ukraine.

The suspect is in detention pending judicial procedures, the two countries' prosecutors said.

"This case underscores the persistent threat Russia poses not only to Ukraine and Ukrainians but to the entire free world," Kostin wrote on X, the former Twitter.

"The Kremlin's criminal regime... organizes and carries out sabotage operations on the territory of other sovereign states," he added.

Polish Foreign Minister Radoslaw Sikorski commended the work of his country's special services and prosecutors in the operation as well as cooperation with neighboring Ukraine.