The Namma Metro Red Line for Bengaluru is still awaiting approval from the Centre despite a revised Detailed Project Report submitted by the state. The Ministry of Housing and Urban Affairs informed the Rajya Sabha that the 37.8 km Hebbal-Sarjapur corridor DPR has been lodged and is under detailed appraisal. The ministry said the project can be approved only after completing mandatory technical and financial evaluation under the Metro Rail Policy, 2017.

The Karnataka government and Bangalore Metro Rail Corporation Limited spent nearly two years revising the proposal and significantly reduced the estimated cost to contain Centre concerns. The revisions brought the estimated cost to Rs 259,990 million, equivalent to Rs 259.99 bn, from a higher earlier proposal after redesigning underground stations, refining alignment and altering station locations. Bangalore Metro Rail Corporation Limited also engaged an engineering consultancy to benchmark construction estimates against similar projects and recommend cost savings.

The appraisal is ongoing and the Centre has not committed to any timeline for approval, noting that decisions are guided by technical feasibility, financial viability and availability of funds. Even after appraisal, the project will require clearance from the Cabinet Committee on Economic Affairs before construction can begin. As a result, the proposed Phase three A corridor remains on hold pending formal Central sanction.

The corridor is regarded as an important link that would connect north Bengaluru with IT hubs in the south east and pass through key residential and commercial areas such as Koramangala and the Central Business District, easing travel across busy stretches. The Centre has committed an equity contribution of Rs 16,950 million, equivalent to Rs 16.95 bn, for Namma Metro Phase three, of which Rs 10,778.9 million, equivalent to Rs 10.78 bn, has already been released. While the project has cleared several technical and cost hurdles, commuters must wait for the completion of formal evaluations before there is clarity on a start date.