Prime Minister Prayuth Chan-ocha's Cabinet approved the steps at a meeting at which all attendees wore face masks and sat 1 meter (3 feet) apart, as recommended by health experts.
The plan to postpone Songkran — the annual three-day traditional New Year's holiday in April — is one of a number of measures to discourage the gathering and movement of large numbers of people. Millions of Thais normally travel from the cities to their hometowns to celebrate Songkran. The holiday will be rescheduled at a later date.
Government-run educational institutions through university will be closed for two weeks starting Wednesday, initially in Bangkok and adjoining provinces.
Gathering places such as bars, karaoke parlors, movie theaters, gymnasiums, boxing stadiums and other sports venues will be subject to closure as ordered by provincial governors. Such venues in Bangkok are to close for two weeks beginning Wednesday.
The closing of restaurants and malls in Bangkok will be at the discretion of its governor. Meanwhile, restaurants are required to implement strict disinfection procedures and health safety measures. Several in Bangkok have already halted table service and are only providing takeout and delivery.
The governors of two provinces, Buriram in the northeast and Uthai Thani in the north, have already regulated travelers with health checks and banned gatherings of more than 50 people.
While the new coronavirus can be deadly, particularly for the elderly and people with other health problems, for most people it causes only mild or moderate symptoms, such as fever and cough. Some feel no symptoms at all and the vast majority of people recover.
Speaking at a news conference after the weekly Cabinet meeting, Prayuth said Thailand remains open to foreign visitors, even though strict conditions apply for people arriving from six places designated by the government as disease-infected zones: China, Hong Kong, Macao, South Korea, Iran and Italy.
Arrivals from those areas must have health certificates issued no more than three days before boarding along with health insurance, and must download cellphone applications developed by the government to keep track of them and their health in Thailand.
Under plans apparently not yet implemented, they would also be required to self-isolate for 14 days after arrival.
Officials have spoken of applying the same rules to people coming from any country with an ongoing outbreak but have not clarified when or how that would be implemented.
Thailand's huge tourism sector is taking a major blow from the COVID-19 outbreak. It accounted for 15.5% of total employment — 5.8 million jobs — in 2017, according to a report by Bangkok Bank.
The government said it would reduce the price of public utilities including water and electricity by 3% to help people and businesses suffering financially.
The government also announced plans to create temporary six-month jobs, but gave no details.
"Under the current circumstances, prevention and protection measures against COVID-19 are the first priority of Thailand," Deputy Prime Minister Wissanu Krea-ngam said Monday when he announced many of the measures proposed to fight the outbreak.
"The effects on the economy, tourism, exports and trade come second," he said. "We don't know yet how serious this battle will be. We are putting in everything to deal with it and then later we will come up with an economic rehabilitation plan."
Thailand, the first country outside China to confirm a new coronavirus case, reported 30 new cases on Tuesday, bringing its total to 177.