Princess Ubolratana Rajaka of Thailand attends "Thailand Hub of Entertainment", a film and entertainment industry event for investors, in Hong Kong.
Thailand's Election Commission on Monday disqualified the sister of the king from running for prime minister on Monday, ending a stunning, short-lived candidacy for a populist party after King Maha Vajiralongkorn called the bid "inappropriate".
That ends a bold gambit by the anti-military coalition to boost its popularity and insulate itself against charges of being anti-monarchy, by having the king's flamboyant older sister Ubolratana run for prime minister, although her nomination can not be legally withdrawn.
The Election Commission echoed the King's royal command issued late on Friday, which said 67-year-old Ubolratana's plan to enter politics - aligned with the powerful Shinawatra clan - was against the constitution.
A staunch royalist and an opponent of former premier Thaksin Shinawatra, Mr Prayut accepted the nomination of pro-military Palang Pracharath Party to be its prime ministerial candidate in the upcoming elections.
The vote, set for March 24, will be Thailand's first democratic elections since ex-Prime Minister Yingluck Shinawatra, who is also Mr Thaksin's younger sister, was ousted five years ago.
In a statement broadcast across Thai television networks, King Vajiralongkorn, 66, said: "Even though she has relinquished her royal titles in writing, she maintained her status and carried herself as a member of the Chakri dynasty". It is unlikely its members would disregard the wishes of the king, who while a constitutional monarch, is considered semi-divine in Thai society. In a statement, the party said it "will move forward into the election arena to solve problems for the country".
Among the candidates for prime minister is the current junta leader Prayuth Chan-ocha, who as army chief led the coup.
'The board agrees that the name of Princess Ubolratana, an educated and skilled person, is the most suitable choice, ' Thai Raksa Chart party leader Preechapol Pongpanich told reporters. Prayuth was the Thai army chief in 2014 and led the coup that ousted a government led by Thaksin's sister.
Parties loyal to Thaksin, a former telecommunications tycoon, have defeated pro-establishment parties to win every election since 2001, but since 2006 each of their governments have been removed by either coups or court judgments.
The Thai royal family, a revered institution shielded from criticism by a tough defamation law, has traditionally been seen as above the political fray, although royals have intervened in moments of political crisis.
Thaksin has lived in self-imposed exile in England since he was deposed.