The government wants to keep the number of referendums concerning any rewrite of the constitution to a minimum to save costs, Deputy Prime Minister Phumtham Wechayachai said on Friday.
Mr Phumtham, who is putting together a panel to design the referendum, said each voting round should cost 3-4 billion baht, and it may take three to four to complete the amendment.
He said his panel, which will comprise representatives from political parties, academics and interest groups, is expected to come up with an option that best follows an earlier court ruling.
In 2021, the Constitutional Court ruled the public must approve any move to amend the entire charter and if that first referendum is approved, another must be held to see if people approve of the new content.
But some pundits say it may take more than two rounds to complete a rewrite, and the public may have to go to the polls if a charter drafting committee is to be directly elected.
Asked about potential panellists, Mr Phumtham said he plans to ask Pongthep Thepkanchana, former chief strategist of Pheu Thai.
He said he has already approached academics, including Ekkachai Chainuwat and Siripan Nogsuan Sawasdee, as well as veteran politician Nikorn Chamnong of the Chartthaipattana Party, all of whom have expressed interest.
Asked if he would talk to legal specialist and former deputy prime minister Wissanu Krea-ngam, Mr Phumtham said he intends to gather input from all sectors but has not had a chance to meet Mr Wissanu yet.
Senate Speaker Pornpetch Wichitcholchai said he disagreed with wholesale changes but said the issue would be decided by the government.