Thailand stands to lose out on foreign direct investment if the second-largest Southeast Asian economy does not seriously address corruption, says former Asean secretary-general Surin Pitsuwan.
"The cost of doing business in Thailand is already 30% higher [because of corruption] before anything can begin. This affects Thailand's image and competitiveness in the region," he said.
However, Thailand Development Research Institute (TDRI) on its website suggested that corruption may be as high as 50% of business costs.
The global economy demands a high degree of accountability and transparency, but Thailand severely lacks both, said Mr Surin.
The lack of these qualities limits Thailand's potential, especially as intra-Asean investment is starting to exceed investment from elsewhere.
"People need to realise that corruption is a cancer that destroys the rule of law and transparency," Mr Surin said.
He suggested that anti-corruption agencies such as the National Counter Corruption Commission need to be strengthened and must be wholly independent with real power to enforce the law. More importantly, they must be free from political interference.
"Every society needs to have a line that it will not go below. That line in Thailand is becoming closer every day. People need to be aware that Thailand is approaching the point of no return and the country could become a corruption black hole in Asean," said Mr Surin.
Pramon Sutivong, chairman of the Anti-Corruption Organisation of Thailand, recently expressed the same sentiment.
"Thailand, right now, is a country on a bus heading towards a cliff and no one seems to know what to do," said Mr Surin.
He also stressed that research and development (R&D) must play a vital role in corporate culture if Thailand wants to escape the middle-income trap. No country can move from being a manufacturing base for other economies without emphasis on R&D.
The 2012 Corruption Perception Index by Transparency International placed Thailand 88th among 176 countries, down from 80th place in 2011, while Malaysia ranked 54th and Singapore fifth.
Mr Surin will speak at the 2013 Bangkok Conference: Global Dialogue on Sustainable Development to be hosted next month by the Thai Chamber of Commerce and TDRI with Caux Round Table, which promotes ethical business.