Before leaving for Cambodia to attend the 21st ASEAN Summit and related meetings in Phnom Penh, Ms Yingluck told reporters that the government has just shown intention to study the TPP but have not yet signed anything.
The Commerce Ministry has been assigned to study the pros and cons and possible impacts that may occur if Thailand signs or does not sign the agreement, she said.
Any talks on the agreement must be based on the country's readiness and potential benefits, she said, adding that the deal must be agreed upon at the cabinet level and required ratification from the Parliament.
There are four counties in ASEAN that have signed the TPP, and Thailand has not made any decision over the issue, she said.
Ms Yingluck also affirmed that she would not raised the TPP issue for discussion with US President Barack Obama when he visited Thailand on Sunday.
The premier also said regarding the preparations to welcome Mr Obama that National Police Chief Pol Gen Adul Saengsingkaew has assured that there would be no problems, particularly with security measures.