MOSCOW (Reuters) -- Russia said Polish lawmakers have dealt a blow to efforts to improve relations by adopting a resolution condemning the Soviet invasion of eastern Poland 70 years ago.
Poland's lower house, the Sejm, unanimously backed a declaration criticizing Moscow's actions before and after the outbreak of World War II in 1939 and urged Russians to cooperate in helping to reveal what really happened.
"The Polish Sejm's adoption of the resolution seriously harms efforts to develop normal good-neighbourly relations between our two countries," the Russian Foreign Ministry said in a statement.
It accused the Polish parliament of trying to politicize "a delicate issue, concerning the feelings of not just Poles and Russians, but Ukrainians and Belarussians as well."
Soviet dictator Joseph Stalin clinched a nonaggression pact with Adolf Hitler in August 1939, paving the way for Nazi Germany's invasion on September 1. Stalin then sent Soviet troops into eastern Poland on September 17.
"In this way, a fourth partition of Poland was accomplished," the text of the resolution said. "Poland became the victim of two totalitarian regimes: Nazism and Communism."
It cited the mass executions and deportations carried out on Polish territory by the invading Soviets as well as the killing of 20,000 Poles in Katyn forest in 1940.
Russians are deeply proud of their country's victory over Hitler in 1945 after a titanic struggle in which up to 27 million Soviet citizens perished. Poland lost about a fifth of its own population, or six million people, during the war.