A woman checks her mobile phone as she walks past a mobile store of Reliance Industries' Jio telecoms unit, in Mumbai, India. Image Credit: Reuters

Shares of Vodafone Idea Ltd. and Bharti Airtel Ltd. surged after the wireless carrier controlled by Indian billionaire Mukesh Ambani said it will end free voice calls on its network.

Vodafone Idea jumped as much as 18%, set for the biggest intraday gain since August, while Bharti climbed 4.8% at 10:48 a.m. in Mumbai. Reliance Industries Ltd.’s shares rose for a third day.

Reliance Jio Infocomm Ltd. will charge customers 6 paise per minute for calls made to rival networks till such time that the telecom regulator moves to a zero termination-charge regime, the company said on Wednesday. Jio users, however, will be compensated with free data of similar value.

The move “seems like a big deal”, as the market has been waiting for Jio to move from a land grabber to focusing on profitable growth,” Chris Lane, an analyst at Sanford C. Bernstein said in a note.

Reliance Jio stormed into the industry in 2016, and became the nation’s top telecom operator after free calls and cheap data lured millions of users and left rivals struggling under mounting debt. Vodafone Idea’s shares, for instance, are down 71% this year despite Thursday’s surge.