Thousands of supporters, mostly wearing red clothes, were gathering near the private jet terminal at Don Mueang airport to welcome Thaksin Shinawatra on Tuesday morning.
They were present together with key figures and MPs of the Pheu Thai Party and an army of local and foreign journalists at the heavily guarded airport.
It was reported that Thaksin was already on his private jet departing from Singapore and his plane was expected to land in Bangkok about 9am.
It would be his first return to the country in 15 years. Authorities planned to take him from the airport to the Supreme Court where he would undergo procedures concerning pending punishment by imprisonment.
Thaksin fled Thailand in 2008, shortly before the Supreme Court sentenced him for helping his then-wife, Khunying Potjaman Na Pombejra, buy prime land in the Ratchadaphisek area at a discount while prime minister.
He faces prison sentences of 10 years in three cases in which he was convicted in absentia by the Supreme Court's Criminal Division for Holders of Political Positions.
