Prime Minister Prayut Chan-o-cha has signalled stricter disease-control measures and a halt to travel easing as the country is grappling with a surge in Covid-19 cases.
In his national address Tuesday evening, Gen Prayut said the situations in Thailand and elsewhere would delay domestic economic recovery.
The latest Covid-19 outbreak in Samut Sakhon province showed that the disease remained a severe threat to the nation and a new strain spreads more easily and quickly throughout the world.
Economies, including Thailand's, will take longer to recover and the country would have to continue restricting arrivals, he said.
"Regarding severe Covid situations outside the country, our biggest threat will be the visitors who can also bring in Covid-19. That would cause problems for the Thai public health system and increasingly damage our economy," the prime minister said.
He confirmed that the country had to intensify disease-control measures.
"I may have to announce more measures. In particular, New Year celebrations may have to be called off," Gen Prayut said.
The Centre for Covid-19 Situation Administration, which he chairs, will introduce more measures this week. "If they remain too lax, the outbreak will cause more economic problems and has nationwide impacts," Gen Prayut said.
The prime minister called on all parties to be responsible and contribute to efforts to control Covid-19 in the country.
Any parties that brought in illegal migrants, be they officials or traffickers, would be decisively prosecuted as most infected people in the latest outbreak were migrant workers, he said.
He promised to speed up the production and procurement of Covid-19 vaccines.
