Airtel: "current VoIP model is not sustainable"

The story of Airtel (and other Indian MNOs) plan to surcharge VoIP services (see "Indian MNOs to Surcharge VoIP Traffic" - here) develops in two directions, as reported by FirstPost: 

As happened in other countries after such intention had been stated (Singapore, Netherlands), the Indian regulator "will look into Airtel’s plan to charge separately for Internet call services (VoIP) offered by