A student-led protest movement has campaigned since last year for the government to step down, seeking a more democratic constitution and for the monarchy to be reformed to make it more accountable.
Hundreds of demonstrators have staged a protest outside Thailand's parliament after Prime Minister Prayuth Chan-ocha and nine ministers survived a parliamentary no-confidence motion after a four-day censure debate.
"It was a disappointment, but expected," protest leader Attapon Buapat said.
Over 1,000 protesters rallied outside the parliament gates on Saturday. Organisers gave assurances the protest would not turn violent.
"We want a peaceful protest," protest leader Panusaya "Rung" Sithijirawattanakul told reporters after speaking to the police. "There is no reason for police to break up this demonstration."
Earlier, lawmakers voted in favour of Prayuth and other ministers, which had been widely expected.
The government is facing allegations it mismanaged the economy, bungled the provision of Covid-19 vaccines, abused human rights and fostered corruption.
But a more serious allegation was that Prayuth has deepened divisions in society by using the monarchy as a shield against criticism of his government.
"We've opened a wound and now will pour salt on it," Pita Limjaroenrat, head of the Move Forward Party told reporters after the vote.
Prayuth, a former chief of the armed forces, overthrew an elected prime minister in 2014 and stayed in office after a 2019 election that his rivals said was badly flawed.
The government has said the elections were free and fair.
Prayuth was expected to survive Saturday's vote due to his coalition government's majority in the lower house.
"The debate went well, but the government must continue its work," Prayuth said in a podcast after the vote. "I would like to ask all Thais to work together to bring the country forward."
The no-confidence motion came as protests returned after a lull brought on by a second outbreak of Covid-19.
"Some 4,000 officers have been prepared," police deputy spokesman Kissana Pattanacharoen said, adding that the rallies were violating an emergency decree to control the coronavirus outbreak. "Police duty is to maintain order," he said when asked if there would be use of force.
Earlier this month, protesters demanding the release of activists scuffled with police.
Youth-led protests last year reached hundreds of thousands, occupying major commercial intersections in Bangkok and spreading to university campuses across the country.
A student-led protest movement has campaigned since last year for Prayuth and his government to step down. They want the constitution to be amended to make it more democratic, and for the monarchy to be reformed to make it more accountable.
“The biggest fault of Prayuth is that he does not understand the principles of the constitutional monarchy,” said Pita Limjaroenrat, leader of the opposition Move Forward Party.
“He used the monarchy to protect himself whenever he was criticized or opposed. This is an evil action, making him no longer qualified to be prime minister,” he said.
His accusation refers to the enforcement of Article 112 of the criminal code, also known as the lese majeste law. Prayuth said in June last year that King Maha Vajiralongkorn had expressed his wish for the government not to use the law against defaming the monarchy to prosecute pro-democracy protesters.
Thanathorn Juangroongruangkit, a popular politician who was forced out of parliament last year, was charged last month with lese majeste for alleging that the government’s procurement of Covid-19 vaccines was late and inadequate and that there was possible favouritism in the awarding of the main contract.
The criticism relates to the monarchy because most of the vaccines that Thailand has ordered are to be produced by Siam Bioscience, a private Thai company owned by the king.
The monarchy is widely considered an untouchable bedrock of Thai nationalism.
The lese majeste law allows anyone to file a complaint with the police, with convictions carrying jail terms of up to 15 years per offence. According to Thai Lawyers for Human Rights, at least 59 people, including several minors, were summoned under the law between November and February.
Four well-known protesters – including human rights lawyer Arnon Nampa, student leader Parit Chiwarak, and political activists Somyos Prueksakasemsuk and Patiwat Saraiyaem – were prosecuted under the law and on sedition charges earlier this month.
Their lawyer requested bail, but the court denied it.