BANGKOK, Sept 5, 2025 (BSS/AFP) - Thailand's influential former prime minister Thaksin Shinawatra said Friday he has left the country by private jet, hours before his party looks set to be ousted from top office.

Thaksin's dynasty has for decades jousted with the kingdom's pro-military, pro-monarchy elite -- but its influence is declining, bedevilled by increasing legal and political setbacks.

In an early-morning post on social media site X, Thaksin said he left Thailand for a medical check-up in Singapore, but diverted to Dubai because of an airport closure and will "visit friends" there as well as meeting respiratory and orthopaedic doctors.

Thaksin's daughter Paetongtarn Shinawatra was sacked last Friday by the Constitutional Court for an ethics breach.

Parliament is set to vote this Friday for her successor -- with a conservative challenger likely to oust the family's Pheu Thai party, which has occupied the top office since 2023 elections.

Meanwhile Thaksin, 76, will next week hear a crucial Supreme Court verdict, which may rule he should not have benefitted from a prison early release scheme.

While his guilt is not the subject of the case, some analysts say the verdict on September 9 could see him jailed.

"I intend to return to Thailand no later than the eighth in order to go to the court in person," Thaksin said on X.

The telecoms magnate was ousted in a 2006 coup and spent 15 years abroad before returning 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.

That sequence of events has prompted the judicial probe into whether he got special treatment.