Thailand's Constitutional Court strikes again, removing yet another prime minister from office.

The country's notoriously interventionist panel of nine appointed judges has ruled that Paetongtarn Shinawatra violated ethical standards in a phone call she had in June with the veteran Cambodian leader Hun Sen, which he then leaked.

In it, Paetongtarn could be heard being conciliatory towards Hun Sen over their countries' border dispute, and criticising one of her own army commanders.

She defended her conversation saying she had been trying to make a diplomatic breakthrough with Hun Sen, an old friend of her father Thaksin Shinawatra, and said the conversation should have remained confidential.

The leak was damaging and deeply embarrassing for her and her Pheu Thai party. It sparked calls for her to resign as her biggest coalition partner walked out of the government, leaving her with a slim majority.