A military-appointed council on Friday approved its final draft of a new constitution that is meant to guide Thailand back to democracy after last year's coup, but faces stiff opposition.
The document will go to a referendum next month, but campaigning is already underway to reject it, a result analysts fear could prompt fresh upheaval in a country rocked by 18 months of political turmoil.
Noranit Sethaputra, president of the Constitution Drafting Assembly (CDA), said 98 members had approved the charter, with no votes against it or abstentions.
"This meeting concluded that the referendum on this draft constitution will be held on August 19," he said.
Some 19 million copies of the 150-page charter will now be distributed to every household ahead of the country's first referendum.
The military, which ousted premier Thaksin Shinawatra last September after months of protests over alleged graft, is pressing hard for voters to approve the charter, which they say will rein in the powers of future premiers.
Elections have been promised by the junta for later this year, but a rejection of the charter could postpone polls.
Although some controversial aspects of the initial draft were watered down, Thaksin's allies said they were determined to quash the new constitution.
"We will ... work together with other groups of activists to educate people and convince them to reject the draft," said Surapong Suebwonglee, spokesman for Thai Rak Thai, the political party formed by Thaksin but officially dissolved in May.
"Compared to 1997 charter, this draft is less democratic," he told AFP.
Shortly after the generals seized power, they tossed out Thailand's 1997 constitution, which had been widely hailed as the most democratic the kingdom had ever known.
The military accused Thaksin of exploiting loopholes in the charter to consolidate power in the prime minister's office and enrich his business empire.
They say the new 309-article charter will improve the system of checks and balances, limiting the prime minister to eight years in office and making it easier to launch impeachment proceedings.
It would also bar the premier from major holdings in private firms, particularly media companies, and expand financial disclosure rules to cover the entire cabinet and the parliament.
Parliament would be slightly smaller, and the Senate would have nearly half its members appointed by a special panel of judges, election officials and civic groups.
Political analyst Thitinan Pongsudhirak called the charter "anti-political parties and anti-politician."
"It's a retribution for the Thaksin years," he said.
Diverse groups are already campaigning to defeat the constitution. Buddhist monks are against the charter because it does not enshrine their faith as a national religion.
Democracy advocates oppose it because the document was written by a military-appointed panel without enough public input.
About 1,500 supporters of Thaksin, who is in exile, joined pro-democracy activists on Friday in front of parliament to urge people to reject the charter, decrying the CDA as a pro-junta.
A spokesman from the Democrat Party, however, told AFP that they would likely back the document.
Analysts say that opposition to the constitution threatens to turn the referendum into a new flash point in the country's raucous politics.
If voters approve the charter, opponents could take to the streets.
If they reject it, the military has reserved the right to impose its own constitution, which could cast doubt on the legitimacy of future elections.
Tensions are already mounting, with Prason Soonsiri, the head of the constitution drafters, on Thursday calling its critics "thugs."
"I want everyone who wants to reject the constitution to explain their reasons why. Otherwise people will not understand, and then they are just like thugs," he said.