The Commissioner of Railway Safety (CRS) is yet to submit the safety certificate of the Tollygunge-Garia Metro route even though Railway Minister Mamata Banerjee had declared on Saturday that the route would be operational by August 23.

While the Metro Railway authorities had requested the CRS to inspect the extension project earlier this month, the CRS has not been able to make it as yet, leading to the speculation that the project may be delayed.

Metro Rail public relations manager Pranab Kumar Dutta said they were waiting for the CRS nod and the route will become operational for commuters after they receive the approval.

The CRS is under the administrative control of the Civil Aviation Ministry and its clearance is mandatory for opening any new railway line for commercial operation.

A senior official of the Metro Rail said trial runs along the line have been conducted since June.

“It will be easy to open the extension line for the public if the CRS cleared it after the inspection,” said an official.

The extension project had started in 1999 and its estimated cost was Rs 1,032 crore, with the state government undertaking 33 per cent of the cost.

The total length of the project is 8.5 km and five stations — Kudghat, Bansdroni, Naktala, Garia Bazar and Briji — have been constructed on the line.