State agencies will report to the cabinet on the pros and cons of joining the Trans-Pacific Partnership (TPP) next week.
The agencies were earlier ordered by Prime Minister Prayut Chan-o-cha to provide the reports, government spokesman Sansern Kaewkamnerd said.
Maj Gen Sansern made the remarks on Tuesday as activists opposed to the US-led trade pact, signed by 12 Pacific Rim countries last Monday, called on the government to study the agreement and appreciate the huge impact it could have on Thailand before rushing to join it.
The state agencies are mainly those in the commerce, finance and industry ministries. A cabinet meeting will discuss the feedback and come up with a stance on the issue.
The US has long courted Thailand to join the partnership but successive governments have been skirting the issue.
Maj Gen Sansern said the private sector has a vested interest in the issue but the government's decision will be made based on "thorough information".
FTA Watch spokeswoman Kannika Kittiiiiwetchakun cautioned: "The government has to make sure it has enough information and a correct understanding before signing the TPP because the pact stands to have a wide range of effects on our country."
She was speaking at a discussion entitled "Should Thailand join the TPP?", organised by the Thailand Health Promotion Institute (THPI) and the National Health Foundation in Bangkok.
"We cannot say now whether we should step in or stay away from the TPP until we know what exact benefits Thailand would gain from participating in the talks," Ms Kannika said.
"Joining the TPP needs very careful consideration," she added.
Jiraporn Limpananon, president of the Independent Organisation for Consumer Protection, voiced concerns that the data exclusivity of the TPP, which will give intellectual property protection to the US biopharmaceutical industry, would bump up the price of medicine in Thailand.
"If we agree with data exclusivity, it could make medicines for serious illnesses, such as cancer, more expensive and Thailand would have to import these more expensive medicines from abroad," she said.
Paisarn Limatit, an academic at Thammasat University's Health Laws and Ethics Centre, said the talks with TPP member countries could weaken the Thailand Tobacco Monopoly.
"Thai courts would lose their power of jurisdiction if any giant foreign tobacco companies like Philip Morris files a lawsuit against the Thai government over its tough tobacco control laws. All cases will go to international arbitration, where transparency still remains questionable," he said.
"If Thailand loses a case, the country will have to pay heavy compensation. Our country will have to shoulder heavier expenses."
THPI president Hathai Chitanon repeated the call he has been making since 2012 that all stakeholders in Thailand should convince the government not to join the TPP.
Dr Hathai submitted a letter and research papers to Gen Prayut last year to back his call.
However, supporters of the pact lauded the TPP for improving access to markets.
Duenden Nikomborirak, research director of the Thailand Development Research Institute, said the pact will trigger a new supply chain effect in which global production for certain industries such as automotive and parts will relocate to TPP member countries to enjoy rules-of-origin advantages. Countries which sign up to the pact stand to gain, while those which stay out could also lose out.
The positive impact on TPP members is expected to accrue mostly to automobiles and parts, textiles and garments, agricultural products, and services -- sectors that will enjoy lower tariffs and more foreign direct investment.
She said not becoming a TPP member will curtail Thailand's competitiveness, as the FTAs Thailand has signed cover relatively small markets.