Metro man E.Sreedharan, in 2013, stressed on the need of a greater expansion of Chennai metro network by undertaking subsequent phases. In December 2016, it was announced that Chennai Metro Phase 2 would be for spreading across 104 stations. In July 2017, in a suo motu statement in the State Legislative Assembly, an extension in Phase II, involving an additional cost of 38,500 million to the original phase II cost of 850,470 million, was announced. This will involve extension of Line 4 from Lighthouse up to Poonamallee, with the Madhavaram–Sholinganallur and Lighthouse–Poonamallee lines intersecting at Alwarthirunagar. The key focus for Phase 2 is to provide a stable connectivity between the northern (Madhavaram, Thiruvottriyur, Redhills) and southern suburbs (Siruseri, Sholinganallur) and the east parts of Chennai (Light house, Mylapore) to the western part of Chennai city (Porur) and also to western suburb (Poonamallee). Tamil Nadu Road Development Corporation (TNRDC) has also proposed an elevated four-lane corridor for the IT corridor from Taramani to Siruseri. CMRL will construct its piers on top of the flyover built by TNRDC.