China has signed rice and rubber purchase deals with Thailand as part of the Thai-Sino railway development agreement.
Negotiations over the railway are continuing.
The deals were signed at the ninth meeting of the Joint Committee on Railway Cooperation in Bangkok on Thursday.
The meeting was led by Transport Minister Arkhom Termpittayapaisith and Wang Xiaotao, the deputy secretary-general of China's National Development and Reform Commission.
The Commerce Ministry signed a deal to sell one million tonnes of rice to the China National Cereals, Oils and Foodstuffs Corporation (Cofco), a Chinese state-owned food conglomerate.
The rice delivered will amount to about 100,000 tonnes a month, starting early next year, according to Commerce Minister Apiradi Tantraporn.
The Rubber Authority of Thailand, meanwhile, signed a deal to sell 200,000 tonnes of rubber to Sinochem, a conglomerate representing the Chinese government, she added.
The rubber deal was agreed upon despite earlier reports the Thai government could put a brake on the rail project after hiccups in the agreement concerning China's rubber purchase, which is included in the package.
A framework of cooperation on the rail development was also signed by the two governments.
The rail routes cover Nong Khai-Nakhon Ratchasima-Kaeng Khoi and Bangkok-Kaeng Khoi-Map Ta Phut.
Transport Minister Arkhom Termpittayapaisith said Thailand had given China additional information about the rail project, particularly the estimated number of passengers and volume of cargo which can be transported on the routes.
Mr Arkhom said Thailand had worked out a work plan for the project to be carried out in the next six months and presented it to their Chinese counterparts, who will review it before giving their suggestions.
"The six-month plan was drawn up as we want the project to materialise quickly, particularly the construction. We will try to make it happen in the middle of next year," Mr Arkhom said.
He said the project value has not yet been decided due to pending estimates by consultancy firms.
The cost is expected to be higher than the original estimate as another train station, Phachi, will be added to the project, he said.
Mr Arkhom said design work handled by China on the Bangkok-Kaeng Khoi section and Nakhon Ratchasima-Kaeng Khoi section is 80% complete and the work could be finished this month.
The two sections will also be built first, he said.
Design work on the two other sections -- Kaeng Khoi-Map Ta Phut and Nong Khai-Nakhon Ratchasima -- is 50% complete, and could be wrapped up by February.
Thai and Chinese representatives also inspected the Chiang Rak Noi train sation in Ayutthaya, where an operations control centre under the Sino-Thai railway development project will be built. The ground-breaking ceremony for the centre will be held on Dec 19.
Meanwhile, Prime Minister Prayut Chan-o-cha insisted the Thai-China railway project will not be derailed as the cooperation inherent in the deal would also underline the 40th year of diplomatic relations between the two countries.
"How long has our relationship lasted? We have to do something symbolic for the 40th anniversary of the relationship between Thailand and China," said Gen Prayut.
He said negotiations on the project must go on.