NEW : Poland welcomes the resolution , foreign ministry says . The 1940 killing of more than 20,000 Polish officers remains a major diplomatic sticking point . This year , a 2007 film about the massacre aired on Russian television for the first time . A declaration says the `` massacre was committed on the direct orders of Stalin '' and that it constitutes an act of genocide against Poland`s Jewish population in occupied eastern Europe during World War II. "
NEW : Poland welcomes the resolution , foreign ministry says . The 1940 killing of more than 20,000 Polish officers remains a major diplomatic sticking point . A declaration says the `` massacre was committed on the direct orders of Stalin '' and that it constitutes an act of genocide against Poland`s Jewish population in occupied eastern Europe during World War II. "