A similar sop is being considered for the owners of old taxis who would upgrade their vehicles to meet environment norms.

"The state of transport system reflects the state of affairs. So, we can't afford to sit back. The transport department is planning changes to keep pace with the changing needs," Chakraborty said at the launch of Kolkata Cab, a radio taxi service.

The minister asserted that his department was keen on addressing the demand for a better mass transit system.

"Given the low road space and the density of vehicles, Calcutta is second only to Seoul in terms of speed. Vehicles here move at an average speed of 25 km per hour. Cops are doing a tremendous job managing traffic in our intricate road network. But we plan to increase the road space soon as the demand for space will shoot up once Nano rolls out," the minister said. On the dais was S. Krishnan, one of the vice-presidents of Tata Motors.

The minister said seven international firms have submitted bids for the proposed ring road that will cost around Rs 8,000 crore. "Work on the 50-km, six-lane road will start at the earliest," Chakraborty said.

The department has also decided to buy 1,000 low-floor buses, each to cost around Rs 18-20 lakh.