The cabinet on Tuesday gave the green light for Bangkok Expressway and Metro Plc (BEM) to kick off the western route project of the Orange Line, according to government spokesman Chai Wacharonke.
The Orange Line transit system connects Bang Khun Non district with Min Buri district through a 35.9-kilometre system of underground and elevated rail sections.
That consists of a 13.4km western route, from Bang Khun Non to the Thailand Cultural Centre, and a 22.4km eastern route, from the Cultural Centre to the Suwinthawongse area in Min Buri district.
Construction of the eastern project has already finished, and trains are expected to begin service by January 2028.
The development of the other project has long been suspended due to an earlier conflict between Bangkok Mass Transit System Plc (BTSC) and the Mass Rapid Transit Authority of Thailand (MRTA) regarding the bidding for the system's concessionaires.
Mr Chai said the Supreme Administrative Court on June 12 dismissed a lawsuit filed by the BTSC against the MRTA, saying the MRTA's bidding committee was legally justified in revising the terms of reference (ToR).
After the case was dismissed, BEM, which operated the MRT's Blue and Purple lines, was given the right to operate the Orange Line. According to Mr Chai, the BEM proposed requiring less financial support from the state than its competitor, Italian-Thai Development (ITD).
Transport Minister Suriya Jungrungreangkit said the government would have the contract signed on Thursday, with an agreement to invest in this 140-billion-baht project in the Public-Private Partnership (PPP)-Net-Cost investment pattern.
The contract, he said, will be effective for 30 years. The western project is set to be completed in 2030.