The Latest on Southeast Asia: Border Row Threatens to Topple Thai Government

Thai and Cambodian troops on May 28 exchanged gunfire at the disputed Chong Bok pass where Thailand’s northeast Ubon Ratchathani province borders Cambodia’s Preah Vihear, leaving one Cambodian dead. Both sides have since pulled back from the disputed area and committed to resolve the issue peacefully but have reinforced their military presence elsewhere along the border. The diplomatic fallout, including Thailand’s tightening of border controls, has significantly strained ties. And this week, Thailand’s governing coalition fractured, threatening to topple Prime Minister Paetongtarn Shinawatra’s government. 

Five days after the border clash, Cambodian prime minister Hun Manet announced that his government would seek a ruling from the International Court of Justice on four disputed border areas. Cambodia won a previous ICJ case over the area surrounding the Preah Vihear temple in 2013, but Thailand does not recognize the court’s jurisdiction. The Thai-Cambodia Joint Boundary Commission (JBC) met in Phnom Penh on June 14 to negotiate border issues but Thailand’s Ministry of Foreign Affairs insisted the commission would not discuss the disputed border areas submitted to the ICJ. The commission is scheduled to meet again in Bangkok in September. 

The ongoing border row has sparked public protests and threats of economic and diplomatic retaliation on both sides. Cambodian Senate president and former prime minister Hun Sen released an ultimatum on June 17 demanding Thailand restore normal checkpoint operations to avoid a full border closure and import ban. But while the Cambodian government has largely read from the same script, factions within the Thai government and military have not. 

Prime Minister Paetongtarn held a private phone call with Hun Sen on June 18, which the Cambodian side promptly leaked. In the call, Paetongtarn adopted a deferential tone, calling Hun Sen “Uncle” and vowing to “take care” of “anything he wants.” More damaging, she told Hun Sen that the commander of Thailand’s Second Army Region, which is responsible for the disputed border, is “aligned with the other side” (her political opponents) and blamed the army for “saying things that aren’t beneficial to the country.”

The domestic political response has been immediate and devastating. Natthaphong Ruengpanyawut, leader of the opposition People’s Party which hold the most seats in the House of Representatives, called on her to dissolve parliament and step down to avoid a coup. Hours later, the Bhumjaithai Party, the second-largest in Paetongtarn’s coalition, withdrew its support for the government and accused the prime minister of “compromising Thailand’s honor, national dignity, people, and military.” It is unclear if the government can still command a majority in parliament or if other members of the coalition will follow Bhumjaithai’s lead. Paetongtarn’s coalition, barely a year in power, is on the precipice of collapse.

Gregory B. Poling is a senior fellow and director for the Southeast Asia Program and the Asia Maritime Transparency Initiative at CSIS. Japhet Quitzon is an Associate Fellow for the Southeast Asia Program at the Center for Strategic and International Studies (CSIS) in Washington, D.C.

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