A month after Srettha Thavisin was sworn in as Thailand’s prime minister from a coalition made up of Thaksin Shinawatra’s Pheu Thai Party and pro-military factions, the real estate tycoon debuted on the world stage at the UN General Assembly in New York. He was chasing high-stakes deals with Tesla, Google and Microsoft, and meeting with other US business leaders in the hopes of turning Thailand into a Southeast Asian economic powerhouse following a decade of military rule.

In New York, Thavisin put on a show of confidence. He is a political leader transitioning from the glamorous high-end property sector to the face of a country moving away from (though not entirely) semi-autocracy under previous PM Prayuth Chan-ocha, who was Thailand’s army chief when he took power in the 2014 coup.

Even though the new Thai government’s priority is the economy, taking a stand on a range of foreign policy issues, including Myanmar, will be inevitable. On this, Thavisin has his work cut out and will have a difficult time reversing the Prayuth government’s legacy on Myanmar, which has damaged Thailand’s image within the Association of Southeast Asian Nations (ASEAN) and beyond.

In July 2022, Thavisin lambasted Prayuth for allowing Myanmar to “breach Thailand’s sovereignty” after a jet flew into Thailand’s airspace while attacking ethnic minority rebels. Thailand did not officially condemn Myanmar for the act and Prayuth as prime minister simply brushed it aside.

It is no secret that Prayuth and Myanmar’s junta leader and head of the State Administration Council Min Aung Hlaing share a close relationship. Min Aung Hlaing has pursued ties with Thai elites for years, asking the late privy council chairman Prem Tinsulanonda to adopt him as a son. After the February 2021 coup in Myanmar, Min Aung Hlaing wrote a letter to Prayuth detailing the reasons behind his actions.

There are other connections, too. Investigations by Thai opposition party Move Forward revealed business ties between Thai Senator Upakit Pachariyangkun and Tun Min Latt, a Myanmar businessman sanctioned by the US government and whose business empire spans arms deals, mining, casinos and energy. He was arrested in Bangkok in September 2022.

In the wider region, the actions of Prayuth’s top diplomat Don Pramudwinai have divided ASEAN. In June, Thailand hosted informal talks among ASEAN’s foreign ministers, including Than Swe from Myanmar. The meeting was boycotted by Malaysia, Singapore and Indonesia, who all insisted Myanmar had to follow through with ASEAN’s five-point consensus, which includes an immediate end to violence and allowing humanitarian aid to reach its citizens. The consensus has so far been a failure.

Pramudwinai’s meeting with the imprisoned former Myanmar leader Aung San Suu Kyi in July, the first such foreign official meeting since the 2021 coup, was seen as a move to upstage Indonesia – the current ASEAN chair – which has been working on a “quiet diplomacy” approach in Myanmar.

Thailand also maintains a formidable economic presence in Myanmar. PTT Oil and Retail Business PCL (OR), a subsidiary of PTT, an energy conglomerate in which the Thai government holds a 51 per cent stake, holds a 35 per cent share in Brighter Energy, a petroleum joint venture in Myanmar. In December 2022, PTT was forced to issue its stance on Myanmar after Norway’s sovereign wealth fund dropped PTT and OR from its equity portfolio in response to the violations of human rights in Myanmar.

In September, Thai opposition MP Kannavee Suebsang appeared to be the lone, and almost inaudible, voice in parliament to press the government to investigate reports of heavily armed Myanmar soldiers crossing the border into Umphang district of Thailand’s Tak province where heavy fighting between the Myanmar military (Tatmadaw) and the Karen National Liberation Army has been taking place. Suebsang said that allowing Myanmar soldiers to cross into Thailand could be interpreted as tacit approval by the Thai military.

The relationship between the Thai military and the Tatmadaw is complex. The Thai military has always argued that a close working relationship with Myanmar matters to national security, especially along the 2,400-kilometre border that is rife with ethnic conflicts, drug, human and wildlife trafficking and various other illegal activities.

Since February 2021, there have been reports of Thai authorities pushing back refugees who are fleeing the fighting in Myanmar. However, thousands of refugees have also been offered help by Thai authorities in border areas. The UN Refugee Agency, citing the Thai government’s records, say that from February 2021 to June 2023 more than 40,000 Myanmar people sought temporary safety in Thailand. Some groups reportedly returned to Myanmar once fighting subsided.

In the 20 months since the coup, more than 6,300 civilians have reportedly been killed in Myanmar. The military’s brutal campaigns – including air and artillery strikes on villages and other populated areas, burning of villages, executions and killings, torture, arbitrary detentions, enforced disappearances, forced displacement, denial of humanitarian access, and persecution – have all been documented.

The Thavisin government might not be as cosy with Myanmar as the Prayuth government, but with no end in sight to the atrocities in Myanmar, the issue will continue to raise doubts about the unity of ASEAN and Thailand’s role in it.