Thai Prime Minister Paetongtarn Shinawatra was suspended by the country's Constitutional Court on Tuesday, while her father went on trial for royal defamation in the latest setbacks for the country's dominant political dynasty.

Thailand's affairs have been driven for years by a battle between the conservative, pro-military, pro-royalist elite and the Shinawatra clan, whom they consider a threat to the kingdom's traditional social order.

Paetongtarn took power less than a year ago and will be suspended while the Constitutional Court investigates whether she breached ministerial ethics during a diplomatic spat with Cambodia.

She told reporters at Bangkok's Government House that she accepted the ruling.

"It's always been my intention to do the best thing for my country," she said. "I'd like to apologise to Thai people who are frustrated about this."

The probe could take weeks or months and Thai media reports said that deputy prime minister Suriya Jungrungreangkit, from her own Pheu Thai party, will initially take charge.

A key opposition politician called for new elections.

Rangsiman Rome, deputy leader of the opposition People's Party -- the successor to Move Forward, which won most votes in the 2023 general election -- told AFP that Paetongtarn had "lost her moral authority" and the ruling was "not surprising".

"Dissolving parliament is the solution."

Separately on Tuesday, Paetongtarn's father Thaksin, the Shinawatra patriarch, arrived at a Bangkok criminal court to face charges of breaching strict lese majeste laws used to shield Thailand's king from criticism.

Thai political analyst Thitinan Pongsudhirak told AFP "there is a direct undeniable linkage between the two cases", and the brand of the Shinawatra family faces "a critical dilution".

- Border clash -

A long-standing territorial dispute between Thailand and Cambodia boiled over into cross-border clashes in May, killing one Cambodian soldier.

When Paetongtarn called Cambodian ex-leader Hun Sen to discuss the tensions, she called him "uncle" and referred to a Thai military commander as her "opponent", according to a leaked recording which caused widespread backlash.

A conservative party abandoned the ruling coalition and around 10,000 people protested Paetongtarn's administration in Bangkok over the weekend.

Her approval rating plunged to just nine percent, down from around 30 percent three months ago, according to a Bangkok university survey.

Conservative lawmakers accused Paetongtarn of kowtowing to Cambodia and undermining the military, and allege she breached constitutional provisions requiring "evident integrity" and "ethical standards" among ministers.

The Constitutional Court accepted the complaint for investigation and said in a statement that by a 7-2 majority it "suspends the respondent from Prime Ministerial duty from 1 July until the Constitutional Court has made its ruling".

Thailand's king on Tuesday approved Paetongtarn's cabinet reshuffle after her allies quit.

She assigned herself the culture minister position and is due to take up the position on Thursday, but it is unclear if she could do so while under investigation.

- 'Critical dilution' -

Her father Thaksin was ousted in a coup in 2006, while his sister Yingluck Shinawatra suffered the same fate in 2014 and other prime ministers from their political movement have been sacked by court rulings.

After 15 years abroad, Thaksin returned to Thailand in August 2023.

He was immediately ordered to serve an eight-year jail term for historic graft and abuse of power charges, but was taken to hospital on health grounds and later pardoned by the king.

The charges against Thaksin stem from a 2015 interview he gave South Korean media and he faces up to 15 years in jail if convicted.

Outside court a dozen of his supporters rallied to support the ex-premier.

"I came here because of the injustice he's faced for so many years," 79-year-old retired physiotherapist Wanlee Iamcharat told AFP. "I believe he didn't do it."

The proceedings are set to last for weeks, with a verdict not expected for at least a month after that.

A court official confirmed to AFP the trial began on Tuesday morning with Thaksin in attendance but said media would not be allowed in.

Outside court his lawyer Winyat Chatmontri told AFP: "I can't speak on his behalf about how he feels, but I think he seems chill."

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(Except for the headline, this story has not been edited by HOOK Desk and is published from a syndicated feed/AFP/AP/PTI.)

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