The blue-chip stock dropped 2.56 per cent to close at Rs 1,062.10 on the National Stock Exchange.
The shares ended 2.12 per cent lower at Rs 1,066.80 on the BSE, after falling as much as 2.6 per cent to Rs 1,061.55. The stock had made a positive opening on the BSE and later pared those gains.
RIL contributed 46.62 points to the 274.94-point decline in the benchmark Sensex to 25,246.25, the most among the index's 30 stocks.
Reliance Industries said it will start offering 4G telecom services next year and unveiled a Rs 1.8 lakh crore investment plan across businesses, aimed at catapulting it into the top 50 companies of the world.
The company will start wireless-broadband services in 5,000 cities and 2,15,000 villages in 2015, Chairman and Managing Director Mukesh Ambani told shareholders.
RIL is is investing Rs 70,000 crore in the telecom business, which will eventually span each of India's more than 6,00,000 villages.