Princess Ubolratana Rajakanya Sirivadhana Barnavadi on Friday upended military-ruled Thailand's politics by becoming the prime ministerial candidate for a party loyal to ousted premier Thaksin Shinawatra.

The elder sister of King Maha Vajiralongkorn has been declared a leading prime ministerial candidate for a party loyal to ousted prime minister Thaksin Shinawatra in a March 24 general election.