Shares of Indian telecom service providers fell on Wednesday after Reliance Jio Infocomm Ltd cut tariffs to counter bigger rival Bharti Airtel Ltd's revision in data plans.
Jio, the telecom arm of Reliance Industries Ltd, said on Tuesday the revision was "a response to Airtel's tariff changes", which would help it maintain "its price leadership".
Bharti Airtel, India's No.1 mobile carrier, revised its data plans earlier this week.
Shares of Airtel declined as much as 6.22 percent to 461.5 rupees on Wednesday, their lowest since Oct. 18, 2017.
Idea Cellular Ltd, India's third-biggest telecom network operator, dropped as much as 5.7 percent to its lowest since Dec. 18, 2017 ahead of its quarterly results later in the day.
Debt-ridden Reliance Communications Ltd slipped as much as 2.2 percent.
Jio entered India's highly-competitive telecom market in late 2016 and disrupted the space with free-voice and cut-price data plans, forcing rivals to match its tariffs and dragging their margins lower.