 He was initially a member of the United Social Democratic Party of Ukraine (SDPU), the party led by Viktor Medvedchuk and loyal to president Leonid Kuchma at the time.Poroshenko left SDPU(o) in 2000 to create an independent left-of-center faction and then a party, naming it Party of Ukraine's Solidarity (PSU).In 2001 Poroshenko was instrumental in creating the Party of Regions, also loyal to Kuchma; the Party of Ukraine's Solidarity having merged into the Party of Regions, Poroshenko launched a new party with a similar name, the party "Solidarity.