The government is easing travel restrictions for citizens from 56 countries to boost the country's pandemic-hit tourism industry, though visitors will be required to undergo a mandatory two-week hotel quarantine.
Tourists from countries including Australia, France and the United States can travel without visas, but would need a certificate to show they are free of Covid-19 72 hours before travel and a booking at a quarantine hotel, Taweesilp Visanuyothin, spokesman for the Centre for Covid-19 Situation Administration (CCSA), said.
Visitors would then be subject to a two-week quarantine period after arriving, he said, adding the normal 30-day visa would be extended to 45 days.
While in quarantine, arrivals would undergo three Covid-19 tests, up from two required previously, Dr Taweesilp said, adding that more testing could potentially lead to shorter quarantine periods in the future.
The revisions come as the tourism-reliant economy struggles to encourage more domestic activity, but an ongoing travel ban continues to keep most foreign tourists away.
Earlier, each arrival was tested twice during 14-day quarantine, first three to five days days after arrival, and then again on days 11-13.
Each arrival is now tested three times, on day 0-1, day 9-10 and day 13-14, Dr Taweesilp said.
The changed testing process would continue until Dec 31. Health officials would then study the results and assess whether quarantine could be reduced to 10 days, Dr Taweesilp said.
The assessment will begin on Jan 1 and is expected to be finalised by Jan 15, he said.
A shorter quarantine is aimed at attracting foreign tourists, he added.
Deputy Prime Minister and Public Health Minister Anutin Charnvirakul previously said the scheme would be for visitors from low-risk countries.
Asked about Christmas and New Year celebrations, Dr Taweesilp said the CCSA was in favour of festivities going ahead and not being banned, as in many Western countries.
However, organisers and attendees must follow disease control measures strictly, he said.
He also said the government was ready to consider companies' disease control measures to allow visiting employees to work during quarantine.
"The entry of tourists will stimulate the economy," Tanee Sangrat, spokesman of the Foreign Affairs Ministry, said.
Travellers from other countries not included in Thursday's announcement could still be eligible for a 90-day special tourist visa and a certificate of entry.
Prime Minister Prayut Chan-o-cha said on Thursday that local authorities can order the cancellation of any New Year festivities that fail to follow disease control measures.
"Strict measures must be in place while people enjoy themselves during the New Year celebrations. I don't want people to suffer from Covid-19 after New Year. Everyone must cooperate for the sake of the country's safety," he said.
Mr Anutin said on Thursday that activities that draw large crowds need approval from the authorities.