Thailand's Constitutional Court has suspended Prime Minister Paetongtarn Shinawatra, who has come under mounting pressure to resign over her leaked phone conversation with former Cambodian leader Hun Sen.

The clip, in which Paetongtarn called him "uncle" and criticised a Thai military commander, sparked public anger and a petition for her dismissal, which the court is now considering.

That would make Paetongtarn the third politician in the powerful Shinawatra clan, which has dominated Thai politics for the past two decades, to lose power before completing their term.

Her ruling coalition is already teetering with a slim majority after a key conservative ally abandoned it two weeks ago.

The Constitutional Court voted 7-2 to suspend her while they consider the case for her dismissal and she has 15 days to present her defence.

In the meantime deputy PM Suriya Jungrungruangkit will serve as the country's acting leader.

If she is eventually dismissed, Paetongtarn will be the second prime minister from the Pheu Thai party to be removed from premiership since August last year.

At that time, her predecessor Srettha Thavisin was dismissed for appointing to his cabinet a former lawyer who was once jailed.

Days later Paetongtarn - whose father is Thailand's deposed leader Thaksin Shinawatra - was sworn in as prime minister.

The 38-year-old remains Thailand's youngest leader and only the second woman to be PM after her aunt, Yingluck Shinawatra.

Already struggling to revive a weak economy, Paetongtarn saw her approval rating fall to 9.2% last weekend, down from 30.9% in March.

She apologised for what she had said in the leaked call, defending it as a "negotiation technique" over recent border disputes. But conservative lawmakers accused her of bowing down to Cambodia and undermining Thailand's military.

The court's decision comes on the same day as Paetongtarn's father, who was seen as the driving force behind her government, battles his own political troubles.

Thaksin is fighting charges of insulting the monarchy over an interview he gave to a South Korean newspaper nine years ago. His trial started on Tuesday.

The controversial political leader, who returned to Thailand in 2023 after 15 years in exile, is the most high-profile figure to face charges under the country's notorious lese majeste law.

Thaksin's return was part of a grand compromise between Pheu Thai and its former conservative foes.

They include the military, which deposed two Shinawatra governments in coups, and groups close to the monarchy.