India’s mobile operators have taken steps to block the service of peer-to-peer calling app Ringo, forcing the firm to suspend local mobile calls, which it launched less than a week ago.

Ringo offers local mobile-to-mobile calls for 19 paise ($0.0028) a minute, which is 69 per cent lower than voice calls on the cellular network, according to Credit Suisse.

Ringo said in a statement that its service is legal and follows all aspects of the Department of Telecom (DoT) and Telecom Regulatory Authority of India (TRAI) regulations. It is working on a “favourable resolution” with operators and has asked TRAI to intervene to unblock its service.

After blocking back-end support for the calling service, the country’s mobile operators are preparing to complain to TRAI that Ringo violates sector rules as it doesn’t operate as per licence requirements, The Economic Times reported.

Rajan Mathews, head of the Cellular Operators Association of India (COAI), told the Times that issues such as masking of calling line identification, security violations and stipulations against reselling will need to be looked into by the regulator.

Bharti Airtel chairman Sunil Mittal suggested that Ringo is “gaming the system”. “I am sure the regulator is already looking at it.”

Ringo continues to offer international calls from India. Its voice service is available in more than 100 countries. It buys bulk minutes through aggregators like Tata Communications, BT and Verizon and then uses its technology to connect the initiator and the recipient via a conference bridge, the Times said. It aimed to have a million customers in three to six months in India.

The country’s mobile players are facing increased competition on two fronts. Voice and SMS revenue has been hit by messaging apps like WhatsApp and Viber, and P2P calling services such as Skype and Ringo. And the already crowded market will soon be more congested when Reliance Rio finally rolls out nationwide 4G service early next year.