"If our allies decide to deploy nuclear weapons as part of nuclear sharing also on our territory to strengthen the security of NATO's eastern flank, we are ready for it," Polish President Andrzej Duda told Polish outlet Fakt in an interview published on Monday.

More than two years of war in Ukraine has spurred NATO countries in eastern Europe"close to Russian territory"to invest heavily in their military strength, although they do not possess nuclear weapons. In the alliance, the U.S., the United Kingdom and France have nuclear weapons, but several European bases host U.S. tactical nuclear weapons.

Russia, which has the world's largest nuclear arsenal, said in June 2023 that it had started transferring tactical nuclear weapons to one of its key allies, Belarus. Russia used Belarus as a springboard for its full-scale invasion of Ukraine. Belarus borders NATO countries Poland and Latvia.

Poland and NATO member Lithuania also border the Russian exclave of Kaliningrad, home to a significant Russian military presence and Moscow's Black Sea Fleet. The Kremlin is "increasingly militarizing" Kaliningrad, Duda said."