Prime Minister Yingluck Shinawatra said the construction of the infrastructure projects over the next seven years would shape the future of Thailand.
The prime minister was speaking at a discussion entitled "Building the Future of Thailand in 2020" at Government House Thursday.
She said the development plan would focus on the construction of electric railways from Bangkok to the provinces and help better connect to neighbouring countries.
"The infrastructure investment is aimed not only at having infrastructure, high-speed trains, double-track railways, roads, airports, border crossings and ports but also at promoting farm products and Otop [one tambon one product]," Ms Yingluck said.
"There will be upstream, midstream and downstream connections from producers to processing plants and export.
"Costs will be cut. Produce will reach consumers faster and in a fresher state. This will attract more investment and people will have more income."
Deputy Prime Minister and Finance Minister Kittiratt Na-Ranong said that despite taking on the massive loan, the government would keep public debt from exceeding 60% of gross domestic product.
The government might not have to borrow the full 2 trillion baht if it was able to convince private participation in the development scheme, he said.
Transport Minister Chadchart Sittipunt said 80% of the investment would go into railways, including four high-speed railways from Bangkok to Chiang Mai, Nong Khai, Rayong and Prachuap Khiri Khan's Hua Hin.
According to the minister, the high-speed railways would take up 39% of the 2-trillion-baht investment.
The government will spend about 400 billion baht on developing electric railways from Bangkok to nearby provinces.
It will also build double track railways with a combined distance of 2,800 kilometres on five routes including from Bangkok to Nong Khai and to Den Chai district of Phrae province.
Other projects in the transport development scheme include four-lane intercity motorways, customs posts and ports.
Mr Chadchart said the government would allow representatives of the private sector's Anti-Corruption Network to examine the implementation of the loan scheme to ensure transparency.
The government plans to take its public relations campaign to people living near development sites.