Former England midfielder Reid has been helping Stoke manager Tony Pulis and intends to return to Bangkok soon, Thai Football Association (FAT) president Worawi Makudi said.
"He did not sign a contract with Stoke. He just helped his friend," Worawi told Thai reporters based in England.
"He cannot go anywhere at the moment because he is still under contract."
Worawi's comments might do little to reassure fans in Thailand, who have received mixed messages about the future of Reid, who signed a four-year contract with Thailand last September.
The former Leeds United, Manchester City and Sunderland boss last week gave interviews with Sky Sports News and the BBC saying he craved a return to the English top flight and was excited by the prospect of becoming Pulis's assistant.
Thai media started speculating about his replacement, with reports suggesting either a recall of previous coach Charnwit Polcheewin, promotion of Reid's assistant, Steve Darby, or even that Reid would double as a coach of both Stoke and Thailand.
