Bolshevik, pan-Slavic party supportive of alliance with Russia and Belarus. Party supports union of all east Slavic peoples into a single Leninist state led by Russia. Party is led by MP Natalia Vitrenko. After the February 24, 2022 invasion of Ukraine by Russia, the PSPU was banned by the National Security and Defense Council of Ukraine on March 20, 2022 for pro-Russia sympathies [Прогресивна соціалістична партія України].