New Delhi, June 15 -- Rare earth magnets, low in cost but critical in function, could emerge as a key supply-side risk for India's automotive sector if China's export restrictions and delays in shipment clearances persist, according to a report by Crisil Ratings.

The rating agency said this week that a disruption lasting more than a month can already impact electric vehicle (EV) launches, affect production, and weigh on the sector's growth momentum.

Rare earth magnets are integral to permanent magnet synchronous motors (PMSMs) used in EVs for their high torque, energy efficiency and compact size. Hybrids also depend on them for efficient propulsion.

The use of rare earth magnets in internal combustion engine (ICE) vehicles is largely l...