The controversial 2001 memorandum of understanding (MoU) with Cambodia to jointly develop parts of an overlapping claim area (OCA) and set a maritime boundary continues to cast a shadow over Thailand.
The OCA, which covers an area of about 26,000 square kilometres in the Gulf of Thailand, is believed to be rich in fossil energy resources.
Under the MoU, the maritime border demarcation and joint development must be carried out as an "indivisible package", with a Thailand-Cambodia joint technical committee (JTC) set up to discuss it.
Several talks have been held since then, but no progress was made, mainly because neither has accepted the other's territorial claim.
The Pheu Thai-led government's plan to revive negotiations with Cambodia has been greeted with scepticism largely due to the close relationship between Thaksin Shinawatra and former prime minister Hun Sen. Hun Sen's visit to Bangkok earlier this year renewed concerns over the controversial MoU.
Calls for scrapping the MoU are now intensifying, pointing to Cambodia's 1972 claim to half of Koh Kut in Trat province.
Critics say the claim contradicts the 1907 French-Siamese treaty, rendering the MoU itself illegal. However, Prime Minister Paetongtarn Shinawatra said the negotiation with Cambodia under the 2001 MoU will resume after a JTC is formed by the middle of this month.
The Bangkok Post asked political analysts to weigh in on the MoU, exploring whether this issue could destabilise the coalition government.
They also discussed the role Pheu Thai should play, especially when the push to resume talks is widely perceived as a result of Thaksin's influence.
Troubles from the start
Panitan Wattanayagorn, an academic in security and international relations, said the 2001 MoU has faced criticism from the start, particularly about how the process was rushed when compared with other agreements.
He argued it should have been a simple memorandum rather than a document imposing obligations. He said it is still unclear whether it includes conditions that Thailand is bound to follow, and the government must clarify this.
The analyst said it does not matter whether the boundary or the sharing of marine resources is negotiated first or whether they are treated as one package; the obligations must be removed.
"Critics claim it will result in a loss of territory, but if that's not the case, the government must clarify what the obligations are, address the implications of Cambodia's territorial claim and resolve them so the document doesn't impose obligations and the talks can proceed," he said.
He said that unless public scepticism is addressed, the MoU will become a political hot potato, noting that parliament might eventually have to revoke the document to defuse tensions.
He suggested the best approach is to engage in talks with Cambodia to revise the content of the MoU to avoid tensions with the neighbouring country.
Mr Panitan said Thai-Cambodian relations have shown signs of improvement since the Preah Vihear dispute, which provides an opportunity for both sides to address sensitive issues.
"It's not wrong for Thaksin to suggest the government pursue talks as the improving relations present a good opportunity, but political parties are turning this opportunity into a crisis," he said.
Mr Panitan warned that if the issues surrounding the MoU strain ties between the two countries, sensitive issues will likely remain unresolved as they have been in the past.
He dismissed concerns the issue will be submitted to the International Court of Justice for a ruling, saying such speculation is premature. Moreover, he said that for a trial to proceed, both parties must consent to participate.
When asked which issue in the MoU he considered the most problematic, the analyst pointed to Cambodia's territorial claim to half of Koh Kut, saying it is not based on any laws.
Mr Panitan also called on government agencies defending the MoU to clarify how revoking it would not benefit the country.
What's at stake
Wanwichit Boonprong, a political science lecturer at Rangsit University, urged the government to spell out the economic benefits of the joint development deal and provide any academic studies that support the claims of 2.2 trillion baht in potential economic value. He said the prime minister's reassurance alone that Koh Kut belongs to Thailand is insufficient.
While most of the public has no doubt about the status of Koh Kut, he said there are growing concerns about the sharing of maritime resources with Cambodia and whether Thailand could be at a disadvantage.
"Claims about the 2.2 trillion-baht economic value have yet to be confirmed by any state agency, leading to speculation that we may be at a disadvantage," he said.
Mr Wanwichit also said public scepticism has intensified due to Thaksin's influence over the Pheu Thai-led government and his strong ties with Cambodia.
He said there is a widespread belief that the relations between Thailand and Cambodia tend to be fragile when the core government party in Thailand is not affiliated with Thaksin.
"The people want to know who stands to gain more from the sharing of benefits from the exploitation of maritime resources. They also want to be assured that [Thailand] will not be disadvantaged. If the government can't address this, it will fuel political tension," he said.
The government coalition partners, he said, may adopt a "wait-and-see" attitude before making a move. He said the objection to the appointment of a political representative as the chairman of the board of the Bank of Thailand is also gaining momentum, and these contentious issues could undermine the government's stability.
Phichai Ratnatilaka Na Bhuket, programme director for politics and development strategy at the National Institute of Development Administration, echoed Mr Wanwichit's comments regarding public beliefs about the Thaksin-Hun Sen relationship.
He said if the MoU is reviewed and revised, there is a possibility the negotiations will succeed. However, he stressed the government must take swift action to address public concerns to prevent tensions from escalating.
'Political agenda'
Pheu Thai Party list MP and former foreign affairs minister Noppadon Pattama said the negotiations with Cambodia are the responsibility of the coalition government rather than Pheu Thai alone.
He said the negotiations will be handled by the JTC, which includes the Ministry of Foreign Affairs' Department of Treaties and Legal Affairs, the Energy Ministry and the military, not Thaksin, and that during the Prayut government, the talks were revived under the MoU framework.
Mr Noppadon said the negotiations tend to go smoothly if the countries involved are on good terms, but stressed the atmosphere is less important than the results, which must comply with international laws. He said the issues related to the MoU should not be politicised as the fallout could undermine not only the government's stability but also national security.
Asked about the Palang Pracharath Party's call for the revocation of the MoU, he shot back, asking why Gen Prawit Wongsuwon, now leader of the PPRP, chaired the JTC for eight years and failed to take action.
"Thais, regardless of their political affiliations, love their country. It's time to end the lies and distortions and speak the truth and legal facts. Stop discrediting because it affects not only the government but also national security," he said.
Mr Noppadon insisted Thailand never recognised Cambodia's territorial claim to half of Koh Kut and it does not affect maritime claims by both countries as they will continue to retain their respective rights if negotiations fail. Cambodia made its initial claim in 1972, which Thailand rejected. The following year, Thailand made its counterclaim.
Mr Noppadon said the misinformation about potential loss of territory is reminiscent of when he was falsely accused of handing over Preah Vihear Temple to Cambodia while serving as foreign minister.
The MoU was signed during the Thaksin government by then-foreign minister Surakiart Sathirathai and Cambodia's Sok An, who was responsible for energy affairs. It was described by the then government as a "very important avenue" for cooperation in hydrocarbons.
Apart from the PPRP, Thai Pakdee Party chairman Warong Dechgitvigrom also called for the revocation of the 2001 MoU and he recently launched a campaign to gather 100,000 signatures to support it.
Panitan: Criticised from the start
Wanwichit: Govt must give evidence
Phichai: Address public concerns
Noppadon: Must not be politicised