The Transport Ministry plans to launch three motorway projects this year, worth 83.52 billion baht.
Transport Minister Saksayam Chidchob said the first project will be the Ekkachai-Ban Phaeo motorway in Samut Sakhon, worth 19.7 billion baht, running 16.4 kilometres.
The cabinet has already approved the project and allocated a budget for its construction.
The State Enterprise Policy Office has proposed to start the bidding for the project in the middle of this year.
The motorway will connect to the 10km Bang Khun Thian-Ekkachai motorway which is under construction and projected to finish in August next year.
The second, the Rangsit-Bang Pa-in motorway, worth 28.13 million baht, will extend 18km from the Utraphimuk Expressway (Don Muang Tollway) and will connect to the Bang Pa-in-Nakhon Ratchasima motorway.
The project is planned to be proposed to the cabinet this year.
The third project, the Srinagarindra-Suvarnabhumi airport motorway, running 18.5km with 35.68 million baht will also be proposed to the cabinet in this year before bidding is called.
Mr Saksayam said Prime Minister Prayut Chan-o-cha would like motorways under construction to be completed before starting new projects.
The ministry will begin operating the SRT Red Line railway, the Bang Sue-Rangsit stretch and the Bang Sue-Talingchan segment, in November while the Pattaya-Map Ta Phut motorway extension has already been opened.