The 22.6km line will connect Thailand Cultural Centre with Suwinthawong in the eastern district of Min Buri, serving 10 underground and seven elevated stations.
Four of the six contracts were awarded to the CKST joint venture of CH Karnchang, Sino-Thai Engineering and Construction, and Unique Engineering and Construction. The remaining two contracts were awarded to Unique Engineering and Construction.
A second 17km phase is planned which will extend the line west to an interchange with the Red Line at Taling Chan.