The over 7-km sub-terrainean stretch will have seven stations.
The first stretch between Alandur and Koyambedu was completed in June 2015 and the second between Chennai Airport and Little Mount in September 2016.
Both these stretches are overground.
The new Metro route is expected to serve more than 20,000 commuters daily, with the fares set to be capped at Rs 70.
Chennai Metro Rail Project Director Rajeev Narayan Dwivedi said that all stages of the project are scheduled to be completed in 2018.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)