
Reid, a former Sunderland manager, is believed to return to the English Premier League to be the assistant manager of Stoke City.
Siamsport online reported that FAT President Worawi Makudi lost his patience with Reid who went to England with him recently. Worawi was in England as guest of the football association.
However Reid refused to Thailand, claiming he wanted to help his friend at Stoke City on a temporary basis.
Worawi returned to Bangkok alone. And the last straw was when Reid informed Worawi that he would like to extend his stay with Stoke City for another two week.
The online said therefore, FAT decided to sack him and the decision will take effect immediately.
Worawi found Reid's refusal unacceptable since he had promised to return to Thailand to resume the job during a meeting with Worawi in Manchester, England about two weeks ago.
Reid's assistant, Steve Darby, is appointed as caretaker coach.
Thailand are set to resume their Asian Cup qualifying campaign against Singapore on November 14 before playing the return fixture four days later in Bangkok.