Prime Minister Yingluck Shinawatra has instructed provincial governors to rustle up support for a referendum on the government's proposed charter amendments, a source said.
Ms Yingluck arrived yesterday in Chiang Mai to attend a meeting of provincial governors nationwide.
The source said the prime minister told the governors to provide information about the referendum to people in their provinces.
The government is likely to call a referendum asking the public if it agrees with the ruling Pheu Thai Party's plan to rewrite the constitution in its entirety.
Pibul Sa-nguanpong, permanent secretary for the interior, said the government had provided governors with policy directions regarding the referendum to ensure consistency.
Meanwhile, Noppadon Pattama, legal adviser and close aide to deposed prime minister Thaksin Shinawatra, said holding a referendum in parallel with amending the charter section by section could be another option.
Mr Noppadon said the parts of the charter that should be altered include Section 237, which covers the dissolution of parties and banning party executives from politics for five years, and Section 68, which allows the Constitution Court to examine the constitutionality of any activities which are regarded as a potential threat to the system of constitutional monarchy.
Section 68 is contentious as some observers question whether the court has the authority to directly receive a petition of complaint from the public.
However, Mr Noppadon said the party will wait until a party seminar at Khao Yai in Nakhon Ratchasima province on Jan 6-7 before making a decision on the issue.
A working panel set up by the cabinet is looking it, he said.
Mr Noppadon said Pheu Thai is unlikely to go ahead with the third-reading vote on the charter rewrite bill pending in parliament.
If it did, Pheu Thai's opponents could seek an interpretation from the court on the issue and the bill could end up being delayed for a year, he said.
PM's Office Minister Varathep Rattanakorn, a member of the working panel on charter amendments and on the referendum, confirmed the panel will come up with conclusions regarding the charter amendment proposals in early January. He said pushing through the third-reading vote is not an option.