Thailand's Constitutional Court removed Prime Minister Paetongtarn Shinawatra from office Friday, ruling that a leaked call with Cambodia's former leader breached ethics standards, in a decision that thrusts the country into renewed political instability and marks another setback for the influential Shinawatra family.

In a 6-3 ruling, the court said Paetongtarn "lacked demonstrable honesty and integrity" and had put private interests ahead of the nation. Judges cited her June phone call with former Cambodian Prime Minister Hun Sen, during which she addressed him as "uncle" and appeared to criticize her own army as border clashes escalated. Fighting erupted weeks later, killing at least 38 people and displacing hundreds of thousands.

The court said Paetongtarn had "caused a loss of public confidence" by showing willingness to comply with Cambodia's wishes. The 39-year-old, who became Thailand's youngest prime minister just a year ago, is the sixth Shinawatra-backed leader to be removed by the military or judiciary in two decades of power struggles between elected governments and conservative royalist elites.

"This is another time that the court's decision has created a sudden political change," Paetongtarn said at a news conference after the ruling. "As a Thai, I love my nation, religion and the king. Thank you everyone who gave me knowledge and experience." She earlier told reporters, "All I wanted was to safeguard the lives of people, whether soldiers or civilians."

Deputy Prime Minister Phumtham Wechayachai will serve as caretaker until parliament selects a replacement. Pheu Thai, the ruling party founded by her father Thaksin Shinawatra, has nominated Chaikasem Nitisiri, a 77-year-old former attorney general, though analysts question his ability to secure coalition backing.

The dismissal also fractured Pheu Thai's fragile governing alliance. Deputy premier Anutin Charnvirakul, leader of the Bhumjaithai Party, withdrew from the coalition over the leaked call and has positioned himself as a contender for prime minister. His party has opened talks with the opposition People's Party, the largest force in parliament, though it has said it would not join a government.

Thailand has a history of abrupt leadership changes. Paetongtarn is the fifth premier in 17 years removed by the Constitutional Court, which has also dissolved multiple parties. Her aunt, Yingluck Shinawatra, was ousted in 2014 before a coup, and her father Thaksin was toppled in 2006 before spending more than 15 years abroad in self-exile.

The ruling comes as Thailand faces sluggish growth, with the central bank forecasting just 2.3% expansion this year. Political uncertainty is expected to delay reforms and complicate coalition dealmaking. "Appointing a new prime minister...will be difficult and may take considerable time ," said Stithorn Thananithichot, a political scientist at Chulalongkorn University. "Pheu Thai will be at a disadvantage."