New Delhi, Aug. 18 -- Maruti Suzuki, Hyundai Motor, TVS Motor Company, and other auto stocks saw a massive rally in Monday's session after the government announced plans for sweeping changes to the goods and services tax (GST) regime. Analysts believe the reforms could revive demand in the auto sector, which has remained muted in recent quarters.

Fourteen out of the 15 constituents of the Nifty Auto index closed with sharp gains, led by Maruti Suzuki, which surged 8.8% to Rs.14,068 apiece, its biggest intraday jump in the last five years. Other major gainers included Ashok Leyland, TVS Motor Company, Hero MotoCorp, MRF, Mahindra & Mahindra, and Eicher Motors, all rising between 2.6% and 8%.

The rally boosted the combined market capitali...