Prime Minister Prayut Chan-o-cha said aircraft were on standby to evacuate Thais from virus-hit Wuhan but China has not given permission, saying it can control the situation.
"China confirmed that it can still control the virus... Flights must be approved by the destination country first... As long as the situation is under control, they are unnecessary. Otherwise, there would be a confusion of flights from other countries," the prime minister said in Nakhon Nayok province on Monday.
He said he had ordered preparations for evacuation flights a month ago and teams of doctors were formed for the task. The Thai embassy in China was compiling a list of Thai people wishing to return home and planning meeting points.
Gen Prayut said the government had the matter in hand and further announcements would be made. Centres would be established to cope with the matter, he said.
Air force chief ACM Manat Wongwat said C-130 planes were ready for a possible evacuation. A flight through Laos and Vietnam to Wuhan would take five hours.
Senior officials were meeting at the Public Health Ministry in Nonthaburi province on Monday to discuss the proper dissemination of information on the novel coronavirus to prevent public confusion.
Deputy Prime Minister and Public Health Minister Anutin Charnvirakul said on Monday there were 200-300 Thai people in Wuhan.
He was confident the coronavirus situation was under control in Thailand because transport from infected cities in China had been suspended, and eight patients found in Thailand had all caught the virus outside the country. There was no human-to-human transmission.
"I confirm that the infected people are under the supervision of the Public Health Ministry and no one has been inappropriately discharged," Mr Anutin said.
He advised people to avoid congested areas and, if they cannot, wear face masks to protect themselves.