Thai Prime Minister Prayut Chan-o- cha said on Friday that the Thailand-China railway project would begin in October as planned.
Prayut was quoted by the Bangkok Post as saying that the project was "historic" and he had ordered Transport Minister Prajin Juntong to speed up the process.
Thailand and China have agreed to jointly build an 867- kilometer dual-track railway line, which will connect northeast Thailand's Nong Khai province, capital Bangkok and eastern Rayong province.
It will be the last section of the railway running through southern China, the Laos and Thailand.
The railway route will use 1.435-meter standard gauge, with trains operating at top speeds of 160-180 kph.
The Joint Committee on Railway Cooperation between Thailand and China has recently concluded its fifth meeting in Thailand, with the next meeting scheduled for early August in China's northwestern city of Xi'an.
The Thai premier is worried about the project as its design and
financing plan are yet to be finalized, Prajin said, stressing conclusions on these matters would be made within August.
A draft bilateral framework agreement on the project, which covers issues like the design, train routes and railway stations, will be discussed at the sixth meeting of the joint committee.
The draft agreement is expected to be finalized by Aug. 21 and submitted to the Thai cabinet in early September.