 After the start of Soviet military occupation in Romania, Haţieganu held the position of PNŢ Minister without Portfolio in the first Petru Groza Romanian Communist Party-dominated cabinet; his appointment, like that of the National Liberal Mihail Romniceanu, followed pressures on Groza to open executive structures to politicians from outside the Communist-led National Democratic Front alliance — both mandates were ended by the 1946 general election.In front of mounting Communist influence, Haţieganu approached Iuliu Maniu with a proposal to establish direct contacts with the Western Allies by having Ion Mihalache evade the country (July 1947); the attempt, known as the "Tămădău Affair", eventually led to the prosecution of the PNŢ leadership during a show trial and to an official ban on all party activities.In November 1948, the authorities of Communist Romania prosecuted and sentenced him to three years in prison for "PNŢ activism" and "sabotage".