The Thai king on Sunday formally appointed Paetongtarn Shinawatra, the 37-year-old daughter of controversial billionaire ex-premier Thaksin, as Thailand's new prime minister.
The court also disbanded the main opposition party, adding to Thailand's ever-turbulent internal politics.
Both were removed from office and forced into exile in coups, although Thaksin returned to Thailand last year as Pheu Thai formed a government.
The king's approval, a formality, was read out by House of Representatives Secretary Apat Sukhanand at a ceremony in Bangkok.