The bitter feud fuelling the border dispute between Thailand and Cambodia

The Guardian

6 hours ago

The dispute over Thailand and Cambodia's contested border, which dates back more than a century to disagreements over colonial-era maps, has broken into conflict before. But the most recent clashes, which erupted on Thursday, have been fuelled by another factor: a bitter feud between two powerful political patriarchs.
Hun Sen, 72, and Thaksin Shinawatra, 76, former leaders of Cambodia and Thailand, were once such close friends they reportedly called one another brothers. Hun Sen has, over the years, supported Thaksin's family during their long-running power struggle with Thailand's military. Thaksin and his sister Yingluck stayed at Hun Sen's home after they were ousted from power, while Hun Sen appointed Thaksin an economic adviser to the Cambodian government. Thaksin frequently visited Cambodia, and Hun Sen was the first foreign guest to see the former Thai leader after he returned home after more than 15 years in self-imposed exile.
But relations have broken down spectacularly over recent months. The exact reasons for their feud are unclear, but analysts say it has created an additional layer of volatility that is exacerbating deadly clashes on the neighbouring countries' border.
Hun Sen and Thaksin are no longer in office in their respective countries, but both remain powerful. Hun Sen ruled for almost 40 years until 2023, when his eldest son Hun Manet became prime minister after running virtually uncontested in a sham election. Thaksin's daughter Paetongtarn Shinawatra became prime minister last year.
The extent of their falling out became clear last month, when Hun Sen leaked a recording of a phone conversation between himself and Paetongtarn.
In the call, which was about the border dispute, Paetongtarn called Hun Sen 'uncle' and told him if there was anything he wanted, she would 'take care of it'. She also made disparaging comments about a senior Thai military commander.
The leaked recording caused uproar in Thailand. Critics accused her of kowtowing to Cambodia, putting her family connections before the country's national interests. She was suspended from office by the constitutional court in July pending an investigation into ethical violations.
It's not clear why Hun Sen chose to turn on his former friends. He has accused Thaksin of betrayal and threatened to reveal further sensitive information about the Shinawatras. 'I never imagined someone so close could act this way,' Thaksin said later, declaring their friendship over.
Some analysts say Hun Sen may be trying to whip up nationalism domestically to increase support for his son, Hun Manet.
Others suggest Hun Sen has been angered by Thailand's efforts to crack down on so-called 'scam compounds' where trafficked workers are held and forced to target people around the world with online scams. This form of lucrative criminal activity has proliferated in the region over recent years, especially in Cambodia.
'The popular narrative in Thailand is that the two men may have had some kind of personal dealings behind the scenes that did not go according to plan and the fallout has spilled over into the realm of national interest,' said Tita Sanglee, associate fellow with ISEAS-Yusof Ishak Institute.
Whatever his motivations, Hun Sen has succeeded in damaging Thaksin's position, exploiting divisions between his family and the military, and creating a power vacuum in Thailand.
Sign up to First Edition
Our morning email breaks down the key stories of the day, telling you what's happening and why it matters
after newsletter promotion
Hun Sen, meanwhile, 'holds near absolute control in Cambodia', adds Tita. He has stamped out virtually all opposition voices and independent media. 'When he chooses to take a strong stance, militarily or politically, it has immediate and direct consequences.'
On Thursday night, Thaksin said he had thanked countries that had offered to mediate the border dispute, but would like to wait, adding: 'We need to let the Thai military do their job, and first teach this cunning Hun Sen a lesson.'
Given Thaksin's weakened position, he may not have a choice but to let the military take the lead.
Last week Thailand downgraded it diplomatic relations with Cambodia, recalling its ambassador, and saying it would expel the country's envoy in Bangkok.
Thaksin has denied the families' feud was the cause of the clashes. However awkward questions about his friend turned foe are likely to continue.
As he visited communities sheltering from the conflict in Ubon Ratchathani, in northeastern Thailand, a woman confronted him: 'You're Hun Sen's friend, aren't you? Is he your friend? Why do you allow Cambodia to shoot Thai people?'
Solving territorial disagreements is difficult in any context, said Pavin Chachavalpongpun, professor at the Center for Southeast Asian Studies at Kyoto University. 'No country would like to sacrifice any inch of sovereignty,' he said. But the personal conflict between Hun Sen and Thaksin has, he added, made their countries' dispute even more unpredictable.
This article was amended on 27 July 2025. An earlier version said Hun Sen ruled Cambodia until 2003; however, his rule ended in 2023.