Thailand witnessed an unprecedented royal drama after the king’s oldest sister announced her candidacy to be prime minister in elections next month, only for the monarch himself to dismiss her move as unconstitutional and inappropriate in a written statement broadcast across the Buddhist nation.

The political party that fielded Princess Ubolratana said Saturday that it would honor King Maha Vajiralongkorn’s intervention late on Friday night, while the princess herself posted a message on her Instagram page thanking people for their support.

Earlier Friday she set off a political earthquake after putting herself forward as a candidate for the populist political movement led by former Prime Minister Thaksin Shinawatra, who is bitterly opposed by many royalists. An unconventional royal who once relinquished many of her formal titles, Princess Ubolratana was seen in some quarters as someone who could broker an end to nearly two decades of political infighting between Mr. Thaksin’s backers and his conservative opponents in the armed forces and civil service.

King Vajiralongkorn’s intervention, though, scuppered their plans and appears to leave the military junta that leads the country in a favorable position as Thailand approaches elections on March 24, the first since the armed forces seized power in a coup five years ago.

Opinion polls regularly place the junta chief, Prime Minister Prayuth Chan-ocha, among the top-ranked candidates after he launched cash handout programs for poor Thais and threw his support behind liberal causes such as the legalization of medical marijuana and same-sex unions. He declared his formal candidacy as scheduled on Friday and will contest the vote against a smattering of other political parties, including another pro-Thaksin vehicle.