SURIN PROVINCE, Thailand — After his daughter was sidelined from political office by a damaging phone call with Cambodia’s leader this month, Thai power broker Thaksin Shinawatra broke his silence to a roomful of politicians and journalists. He had a stunning message to deliver: His decades-long relationship with Cambodian strongman Hun Sen was over.
“I used to be close to him — like brothers,” Thaksin said. “But after what he did to my daughter, I was shocked. How could this even happen?”
For years, many had believed that the personal relationship between Thaksin, 75, and Hun Sen, 72, would be the glue holding the two neighbors together despite an intractable border dispute. Both were among Southeast Asia’s most seasoned politicians, bound by a friendship spanning 33 years and by their shared dynastic ambitions, with children who were elevated to power within a year of each other.
Now, a rift has opened up between the two men, bewildering even Thaksin himself and shocking insiders. And the fallout has been severe, with Thai and Cambodian troops exchanging fire in the deadliest clashes in over a decade. Analysts say they worry that the animosities could spiral out of control.
“I was surprised how two close friends for so many years ended up practically overnight in such an escalation,” said Kantathi Suphamongkhon, who was Thailand’s foreign minister from 2005 to 2006 when Thaksin was premier. “This is something that I never expected — how that friendship can break apart so spectacularly.”
On Friday, clashes at the border entered their second day, sending thousands fleeing from their homes and bringing the death toll to at least 16 people. Cambodian officials reported Thai strikes at seven sites, and a Cambodian military convoy was seen moving ammunition toward a contested temple, suggesting that de-escalation was not imminent.
In the hours after fighting began Thursday, Thaksin and Hun Sen lobbed insults at each other on social media. Thaksin said many countries had offered to mediate but that he wanted to “let the Thai military do their duty to teach Hun Sen a lesson about his cunning ways first.”
Hun Sen fired back at Thaksin on Facebook while referring to himself in the third person: “Now, under the pretext of taking revenge on Hun Sen, he is resorting to war, the ultimate consequence of which will be the suffering of the people.”
Analysts say Hun Sen has sought to exploit the turmoil within the Thai government to shore up his own legitimacy. Even opposition figures in Cambodia have taken the government’s side, arguing that the disputed temples that lie along the border belong to the country. A crisis can also help solidify the nationalist credentials of Hun Manet, the current prime minister and Hun Sen’s son, who has implied that Cambodia’s one-party rule is better than the domestic chaos in Thailand because there is “no confusion or conflicting orders.”
The political standing of Thaksin, a billionaire tycoon, and his ruling Pheu Thai party have both weakened since he struck a deal with the royalist-military establishment in 2022 to end 15 years of exile, alienating some of his core supporters. Despite that deal, in recent months, the Thai government has appeared increasingly at odds with the country’s powerful military.
And while he is still the most influential person in Thai politics, Thaksin’s hold on power is tenuous — he is fighting a criminal royal defamation charge that could send him to prison for as long as 15 years.
For decades, Thaksin and Hun Sen worked to anchor their personal and political fortunes together. In 2001, they signed a memorandum of understanding to pursue the extraction of oil and gas in the Gulf of Thailand. But that plan ultimately fizzled because of resistance from Thaksin’s rivals.
Hun Sen and Thaksin remained close even after Thaksin was ousted in a 2006 coup. Hun Sen appointed Thaksin as an economic adviser to the Cambodian government, and allowed him and his sister, Yingluck, who was also overthrown in a coup, to seek refuge in his home in Cambodia. Hun Sen later said he named the bedrooms the “Thaksin room” and the “Yingluck room.”
In Thailand, though, this closeness with Hun Sen has often been regarded with suspicion by Thaksin’s political opponents, particularly those in the military and conservative establishment. Thaksin has never been able to shake off the view held by many that he is interested only in his personal gain.
“The aspirations and the dream of wealth of the two families have not been realized,” said Kasit Piromya, another former foreign minister of Thailand. He said Hun Sen probably saw this as a failure on Thaksin’s part. “Hun Sen was in total control of his country, and he could carry out his end of the bargain. But Thaksin has been losing that luster and control of the Thai society for the past 20 years.”
After Thaksin returned to Thailand in 2023, he increasingly positioned the country to be an economic competitor to Cambodia. He floated the idea of an entertainment complex that would rival the casinos in Cambodia, a lucrative source of revenue for Hun Sen and his fellow tycoons. Analysts say Hun Sen was probably feeling threatened by Thailand’s warning to cut off electricity in the border area and its subsequent arrest warrants against tycoons operating casinos and online scam compounds in the area.
The relationship between the two historical rivals has long been fraught because of the dispute over the undefined 500-mile-long border as well as over claims to ancient temples. In 2003, Cambodians rioted in the capital, Phnom Penh, after a Thai actor was reported to have said that Angkor Wat, the Cambodian temple, belonged to her country.
Much of the fighting has centered around the 11th-century Preah Vihear temple. The International Court of Justice awarded the temple to Cambodia in 1962, but Thailand has continued to claim the surrounding land.
According to Kantathi, Hun Sen in 2006 invited Thaksin to make a friendly visit to the Preah Vihear temple and land a helicopter near it.
Kantathi said he urged Thaksin not to go, warning that Cambodia could use the visit to strengthen its territorial claims to the areas claimed by both Cambodia and Thailand. A visit by a Thai prince in the early 1930s, when Cambodia was a French colony, was later cited by Cambodia to bolster its argument at the International Court of Justice, he said. (The Thai prince did not complain about the hoisting of the French flag during his visit, which the court said amounted to his tacit consent to French-Cambodian control.)
Thaksin ultimately canceled the trip.
The proposed trip has not been made public, but Jakrapob Penkair, a longtime associate of Thaksin, confirmed that Thaksin had told him about it.
Thaksin could not immediately be reached for comment. Hun Sen’s office did not immediately respond to a request for comment.
The dispute over the temple escalated significantly in 2008 when Cambodia listed Preah Vihear as a UNESCO World Heritage Site, leading to deadly military encounters in 2008 and 2011.
This year, tensions rose again when Thai and Cambodian soldiers clashed briefly, killing a Cambodian soldier in late May. Two weeks after that, Thaksin’s daughter and the then prime minister of Thailand, Paetongtarn Shinawatra, tried to call Hun Sen to discuss the crisis.
She was unable to reach him, but Hun Sen later called Paetongtarn’s personal number, according to Thaksin, who recounted his version of the events at a seminar in Bangkok.
Three days later, Hun Sen posted the audio recording of that call on Facebook. The Thai public heard Paetongtarn calling Hun Sen “uncle” and telling him to ignore “the opposite side,” a reference to the Thai military.
It led to calls for her resignation and multiple complaints. One complaint filed by 36 senators at the Constitutional Court led to her suspension this month.
Thaksin said, “I was wrong to trust someone like Hun Sen.” Upon learning that 12,000 Cambodian troops had been mobilized to the border last month, he called the translator who had facilitated his daughter’s call with Hun Sen and told him: “You tell your boss — our children are prime ministers of both countries. Are we going to war now?”
Thursday’s clashes may have been an indication of the dangerous direction the two countries are heading. Thailand said Cambodia fired rockets into civilian areas and that it responded by sending F-16 fighter jets to bomb targets in Cambodia — a rare deployment of the jets for combat in the region. Cambodian officials said Thai soldiers had opened fire on Cambodian troops first, at a temple.