Economists have questioned the transparency of the government's bill to borrow 2 trillion baht to finance infrastructure investment megaprojects.
Nualnoy Treerat, a lecturer at Chulalongkorn University's economics faculty welcomed the investment programme but voiced concern about the investment methods.
She disagreed with the government's plan to be the sole investor in the investment programme by seeking the 2-trillion-baht loan.
The long-term debt means the country will miss out on other investment opportunities in the future, she said.
The programme will be financed under a decree authorising the government to borrow 2 trillion baht over the next seven years, with repayment made over the next five decades.
The government should allow the private sector to invest in some of the projects to help reduce debt burdens and the risks involved, she said.
Ms Nualnoy said private companies would be able to study whether the projects are worthy of investment and would be better able to avoid losses.
Giving private investors an opportunity to invest in the megaprojects will boost public confidence in the projects, she said. There is no guarantee the government will manage the projects efficiently.
The government must break down the details of the projects to show which ones should be undertaken by the state and which ones should go to private firms, Ms Nualnoy said.
She said the government must also disclose information about the projects to ensure transparency.
Sakon Waranyuwattana, a lecturer at Thammasat University's economics faculty, said the government's option to seek the massive loan would boost debt and is unwarranted.
The programme could be financed through the normal budget, Mr Sakon said. Under the borrowing bill, the money represents extra-budgetary spending and the details of the projects could be changed to suit the needs of politicians.
Under the conventional budget law, state spending programmes cannot be changed once they have been settled on, he said.
Somchai Jitsuchon, research director at the Thailand Development Research Institute, also questioned the investment programme.
Without strict legal enforcement, the spending will be "a blank cheque", Mr Somchai said.
The bill does not specify if parliament has the authority to scrutinise the spending of the projects, he said.
Vichai Assarasakorn, vice-chairman of the Thai Chamber of Commerce, said the private sector expects the government to provide clearer details about the projects once parliament endorses the bill.
"The budget is huge," he said. "We expect to see transparency in the investment. It is critical for the public to be able to monitor the allotment and disbursement closely."