MUMBAI (Reuters) - India's richest man Mukesh Ambani is likely to announce on Tuesday that Reliance Industries' <RELI.NS> has reached its targeted 100 million subscribers on its Jio telecom unit, a source familiar with the matter said.
Ambani could also make additional announcements, the source added without giving details, when he starts speaking at 1330 India time (0800 GMT). The speech will be broadcast live on the company's social media accounts.
Reliance Jio Infocomm Ltd opened for business in September and has shaken up the competitive Indian telecoms market with its free voice and cheap data plans that are slated to run through the end of March.
Ambani has already hinted Jio surpassed the 100 million subscriber mark in comments at a tech industry conference last week.
"When we started Jio and we set a target for ourselves in terms of saying that we will acquire a 100 million customers in the shortest time, even we didn't imagine that we will do it in months in terms of that," Ambani said at the time.
Concerns, however, remain if Jio will be able to retain its subscribers once it begins charging for the services. Analysts say many subscribers are using Jio as a second mobile connection to take advantage of the free data.
Jio's launch came after years of delay and Reliance Industries has already invested more than $20 billion into the venture.
Shares of some of Jio's rivals fell ahead of Ambani's speech, with Bharti Airtel <BRTI.NS> down 2.2 percent. Idea Cellular <IDEA.NS> fell as much as 1.1 percent but recovered to gain 0.41 percent later in the day.
Bharti Airtel and Idea are India's largest and third-largest telecoms network operators, respectively.
The competition posed by Jio is cutting profits across the sector, with Bharti Airtel reporting its lowest profit in four years in the October-December quarter. Idea posted its first ever quarterly loss over the period.
Jio's emergence has also spurred consolidation in the sector with Idea and Vodafone Plc's <VOD.L> Indian unit, the market's second biggest player, beginning talks for a planned merger of their operations.
(Reporting by Sankalp Phartiyal and Devidutta Tripathy; Editing by Himani Sarkar)