Since the government has huge stocks of pledged rice that it has received from farmers and which it is now having problems selling, Chula Sukmanop, director-general of the Office of Transport and Traffic Policy and Planning, said it may not be possible to barter the rice for the high-speed railway project.
The government should seek loans to pay for the railway, because that would enable it to select suitable technology for the high-speed trains, he said in Phitsanulok on Tuesday.
Mr Chula was visiting the province to open the first public hearing on the Phitsanulok-Chiang Mai high-speed railway section.
It is the second phase of the Bangkok-Chiang Mai high-speed railway plan. The session drew about 200 people from Phitsanulok and the nearby provinces of Sukhothai and Uttaradit.
Mr Chula said the design and public hearings on the first phase of the project, which will cost an estimated 240 billion baht, from Bangkok to Phitsanulok, are completed and the environmental impact assessment is underway.
The 147-billion-baht second phase is currently being designed.
Phitsanulok will be a major station for the project and there are three optional routes from Phitsanulok to Chiang Mai.
The first route runs along the existing northern railway track but the construction will be difficult and costly because it involves going around and through mountains, which requires building tunnels and bridges.
The second proposed route runs mostly along the existing rail tracks but deviates slightly to pass near the centre of Phrae province.
The third proposed route will be a new line running through Si Satchanalai district of Sukhothai and Lampang.
Mr Chula said he supports the high-speed railway development.
He noted the cost of such projects are rather high, the equivalent of about four years' worth of the road building budget.
Also, the rail projects may not be finished on schedule as Thailand has not improved its railway system for a long time.
The government plans to spend 2.2 trillion baht to develop transport systems but the spending needs approval from the next government following the House dissolution late last year.
The transport planning director-general said that if the 2-trillion-baht borrowing plan to fund the train development is turned down, the government should find money through other methods to pay for transport projects.
There are 54 projects under the 2.2-trillion-baht transport scheme, Mr Chula said the first phase of the high-speed railway from Bangkok to Phitsanulok, which he considered to be highly feasible, should get immediate priority.
He also gave an assurance the high-speed railway projects on three other routes would proceed.
They are from Bangkok to Nong Khai, Prachuap Khiri Khan (Hua Hin district) and Rayong provinces.