"We are very close. It is a matter of one or two million (subscribers). Maybe, by next few weeks or months, we should be there," Bharti Enterprises Managing Director Manoj Kohli said on the sidelines of an IMI event here.
At the end of April, Airtel had over 297 million customers across 20 countries. The latest global ranking and subscriber numbers were not immediately available.
According to analyst firm Wireless Intelligence, the telecom major became fourth largest operator in the world with over 250 million subscribers in Q2 of 2012.
Bharti Airtel had become the 5th largest mobile operator in the world following its acquisition of Zain Group's mobile operations across 15 African nations in June 2010.
Kohli said Airtel has invested Rs 1.70 lakh crore so far and has annual revenues of over Rs 85,000 crore.
He said that in 2002, Airtel innovated the concept of outsourcing which later became a norm for telecom operators across the world.
"We decided in 2002 to concentrate on things that we know and outsource the work, which we don't know to our partners," Kohli said while addressing the students of IMI.
He said Airtel outsourced the network part to Ericsson and Nokia and IT services to IBM, which became a very successful model.