After the coup, with Shinawatra and key party executives either abroad or arrested, Chaisang became the acting party leader after Sudarat Keyuraphan declined to do so.
The Thai Rak Thai was registered on July 15, 1998, by telecommunications entrepreneur Thaksin Shinawatra and 22 other founding members, including Somkid Jatusripitak, Thanong Bidaya, Sudarat Keyuraphan, Purachai Piumsombun, Thammarak Isaragura na Ayuthaya, and Prommin Lertsuridej.