Coalition partner, the United Thai Nation Party (UTN), voiced opposition to the attempt by the ruling Pheu Thai Party and the main opposition People's Party (PP) to amend parts of the 2017 constitution, including one concerning the ethical standards to which political officeholders are held.
The original intention of Sections 160(4) and (5) of the 2017 charter, for instance, is to keep people who do not meet certain moral standards from obtaining power in public office, Thanakorn Wangboonkongchana, deputy leader of the UTN, said on Friday.
Any attempt to undermine this could make it easier for those lacking in scruples to rise to power, he said.
"While there is an extremely urgent need to change parts of the charter, what is more urgent now for the government is improving the economy," Mr Thanakorn said.
"Parliament is encouraged to ponder this issue carefully before making any further decisions," he added.
"If both the House of Representatives and the Senate press ahead with amending the charter's ethics section, they could be seen as doing so for their own interests."
Worse still, if anyone attempts to block this move to amend the charter by filing petitions, they risk being found guilty of violating the law by pushing for such a self-serving legislative amendment, Mr Thanakorn said.
He was responding to Pheu Thai's submission of its partial charter-amending bill to the House on Wednesday, which followed last week's submission of a similar draft by the PP.
He said the 2017 constitution, approved in a referendum, is an effective way of suppressing corruption and misconduct.
House Speaker Wan Muhamad Noor Matha said the deliberation of the two bills in the Lower House would likely begin around mid-October if not earlier, but not later this month as was previously speculated.
PM's Office Minister Chusak Sirinil, speaking in his capacity as a deputy Pheu Thai leader for legal affairs, dismissed claims the party has a hidden agenda.
The party has been accused of attempting to help former premier Thaksin Shinawatra, the de facto leader of the party, to officially become a party member again so that he could avoid facing a legal probe into his alleged inference in the ruling party's internal affairs.
Mr Chusak said Pheu Thai's charter-amending bid is instead aimed at ensuring equal rights for all Thais in becoming a member of any political party of their choice, by eliminating what he described as an over abundance of restrictions.
At present, even those who have received suspended jail sentences are barred from joining a political party, which he described as being unjust.
Mr Chusak also confirmed Pheu Thai is seeking to amend the organic law on the National Anti-Corruption Commission (NACC), to eliminate the latter's authority to bypass the prosecution and bring cases to court on its own, in the event the two bodies are unable to find common ground on the case.
Pheu Thai also aims to amend the organic law on political parties, said Mr Chusak.
Nakharin Mektrairat, president of the Constitutional Court, declined to comment on the two parties' bid to amend the charter, which is seen by some critics as a development that could lead to changes to the court's role.
In other news, Deputy Prime Minister Phumtham Wechayachai, speaking in his capacity as a government whip, said Pheu Thai is seeking to meet with all coalition members to discuss the party's charter-amending proposals before Sept 27. A consensus among all these parties is required, he said, adding that he was unable to say at this point whether all of the coalition partners would support the bill.
The partial amendment would be pushed in parallel with the government's move to rewrite the constitution.
