File photo: Anil Ambani of Reliance Group

Anil Ambani-controlled Reliance Communications is in talks with Russia's Sistema for a potential merger of their India telecom businesses, the company said in a statement to the Bombay Stock Exchange. The merger could take place through a share swap."The discussions are indicative and non-binding in nature, and remain subject to due diligence, definitive documentation and approvals, as may be necessary. There is no certainty that any transaction will result," said Reliance Communications, India's fourth-biggest mobile carrier by customers.Russia's Sistema holds the majority stake in Sistema Shyam TeleServices which operates its telecom services under the MTS brand in India. Shyam Group of India is the Indian partner in this venture.The announcement comes days after elder brother Mukesh Ambani set December deadline for launching his 4G phone services. Cash-rich Reliance Industries' entry into the crowded telecom sector is a potential threat for established players such as Reliance Communications and Bharti Airtel, analysts say.RIL has spent more than $15 billion for the digital business to date, including the Jio 4G venture. Reliance will offer its 4G services for as little as Rs 300 a month.Reliance Communications shares closed 0.6 per cent higher at Rs 58.85 on Monday, in line with the Sensex, which gained 0.6 per cent.