Arrest warrants will be shown to former prime minister Thaksin Shinawatra once he arrives in Thailand, before he is taken to serve jail time.
Thaksin's return from self-imposed exile is scheduled for Tuesday, the same day parliament will meet to select the country's 30th prime minister.
Paetongtarn "Ung Ing" Shinawatra, his daughter and also a Pheu Thai prime ministerial candidate, posted on social media that her father was scheduled to land at Don Mueang airport aboard his private jet on Aug 22 at 9am.
Thaksin and his sister, Yingluck, reportedly left Dubai for Singapore and he was to depart for Don Mueang airport on Tuesday.
According to a source, officials will wait for Thaksin's arrival at the VIP landing zone.
Upon his arrival, Thaksin will be shown all arrest warrants and other related documents by senior police before being escorted through immigration and then on to the Police Club on Vibhavadi Rangsit Road before he reports to the Supreme Court.
Thaksin fled Thailand in 2008, shortly before the Supreme Court convicted him for helping his then-wife, Khunying Potjaman Na Pombejra, buy prime land in the Ratchadaphisek area at a discount.
Thaksin posted on X (formerly Twitter) that he had originally planned to return to Thailand by Aug 10, but that plans for a medical checkup meant a delay of two weeks.
Thaksin faces jail 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.
Supporters of the United Front for Democracy against Dictatorship (UDD) from several provinces will also travel to Don Mueang airport to greet Thaksin, their leaders said on Sunday.
Mayuree Sawetasai, a red-shirt leader in Ayutthaya province, said about 500-800 local supporters would leave on Monday night along with between 200-300 more red-shirts from Nakhon Phanom province.
More groups will arrive on Tuesday, she added.
Thaksin's party Thai Rak Thai and its successors have won every election since it came power to 2001 -- except for this year's poll, when Pheu Thai narrowly lost to the Move Forward Party.