Mumbai, Nov. 14 -- A simmering rift between India's top automakers over upcoming emission norms has burst into the open from behind closed doors. Tata Motors Passenger Vehicles Ltd on Friday publicly rejected calls for easing norms for small cars, directly countering market leader Maruti Suzuki India Ltd's long-standing demand for relaxed standards.

Shailesh Chandra, managing director of the Mumbai-based carmaker - and president of industry lobby Siam (Society of Indian Automobile Manufacturers) - said on the sidelines of the company's Q2 earnings that there was "no justification" for any relaxation in the next phase of emission norms for small cars.

He further warned that redefining small cars based on weight rather than the current cl...