The Kremlin said on May 10 that Poland's decision to rename the Russian city of Kaliningrad in its official documents was a "hostile act," as bilateral ties continue to fray over the war in Ukraine. Kaliningrad was annexed by the Soviet Union and renamed to honor Soviet politician Mikhail Kalinin. Warsaw referenced Kalinin's connection to the 1940 Katyn massacre, in which Soviet forces executed thousands of Polish military officers, and said the city should be referred to as Krolewiec, its name when it was ruled by the Kingdom of Poland in the 15th and 16th centuries. To read the original story by Reuters, click here.