A senior member of the Bulgarian Socialist Party (BSP), Petkov was appointed interior minister in the Socialist-led three-way coalition government that took office in the Balkan nation after inconclusive parliamentary elections in June 2005.
Petkov, inače visoki funkcioner Bugarske socijalističke partije (BSP), imenovan je za ministra unutrašnjih poslova u tročlanoj koaliciji Socijaličke vlade koja je preuzela vlast u zemlji posle parlamentarnih izbora u junu 2005, kada nije bilo ubedljivog pobednika.