However, the opposition party admits its enthusiasm for opposing the amendment at the joint sitting of parliament is unlikely to be matched by fervour on the streets, where anti-government protest groups have been gathering.
The Democrats admit the amendment attempt is unlikely to stoke anti-government protests further as it involves legal jargon that is simply too complex for "ordinary" people to understand.
Most of the protesters on the streets _ some of whom have threatened to march on Government House _ are more concerned with bread and butter issues such as the cost of living, he said.
The Democrats' chief whip Jurin Laksanavisit said yesterday they will not approve the amendment as the process and the content of the draft to change the section have problems.
Amending Section 190 would change the current requirement for some international contracts to be approved by parliament.
In its current version, Section 190 requires all deals involving issues of sovereignty to be ratified by parliament.
The amendment process was flawed from the beginning as the meeting to deliberate it in its first reading was short of a quorum, Mr Jurin said.
The draft gives the executive branch more power to make agreements which could benefit certain groups or individuals while reducing the power of the legislature, Mr Jurin said.
He claimed the government has two hidden agendas in wanting to make the change.
It is intended to benefit certain energy businesses and to acknowledge the signing of the Preah Vihear joint communique by former foreign minister Noppadon Pattama without parliamentary approval in 2008, Mr Jurin said.
The Supreme Court's Criminal Division for Holders of Political Positions in April accepted for consideration a negligence charge filed against Mr Noppadon by the National Anti-Corruption Commission.
The commission had accused him of negligence after he signed the communique with Cambodian Deputy Prime Minister Sok An while he was foreign minister in the Samak Sundaravej government.
The Constitution Court had previously ruled the joint communique, which backs Phnom Penh's request for the listing of Preah Vihear as a Unesco World Heritage site, needed parliamentary approval.
Mr Jurin said the opposition will point out the impacts the amendment will have on the public, although he said the amendment is unlikely to escalate the ongoing anti-government protest.
Democrat list-MP Ratchadaporn Kaewsanit said she had visited the protesters at the Uruphong intersection and found that they had little interest in the amendment of Section 190 of the charter as the issue was not discussed on stage at the rally site.
This is probably because the section involves legal terminology, which is too complex for ordinary people. "They think the issue is irrelevant to their everyday lives," Ms Ratchadaporn said.
But she insisted that changing the section will have a direct impact on the public as any international agreements and treaties which the government reaches with other countries will affect domestic affairs.
She said the amendment will allow some international contracts to bypass parliamentary scrutiny, which could put the public interest at risk.
Pheu Thai Party spokesman Prompong Nopparit said yesterday deliberation of the amendment is expected to take only one day. The amendment draft has only four sections.
He said the anti-government protests should not affect the parliamentary debate as the peace-keeping command set up to handle protesters has guaranteed it can control the situation.
National Security Council secretary-general Paradorn Pattanatabut said yesterday security reports indicated that the various anti-government protesting groups are actually linked together.
They include the People's Democratic Force to Overthrow Thaksinism at Lumpini Park, the Network of Students and People for Reform of Thailand at Uruphong and the People Assembly Reforming Thailand based at Rangsit University.
These groups are also mobilising other anti-government protesters such as the white-masked V for Thailand movement and rubber and oil palm protesters in Nakhon Si Thammarat to join the protests in Bangkok today and tomorrow, Lt Gen Paradorn said.
The government cannot let its guard down, he warned.
Deputy secretary-general to the prime minister Thawat Boonfueng said the Internal Security Act (ISA) will remain in force until Friday.
The ISA may be extended if the protest gets out of hand, he added.
He insisted the government will not permit protesters to rally outside Government House or parliament.