An official with India’s telecoms regulator has stated that Bharti Airtel’s sponsored content data service, as well as other operators’ zero-rating access deals with Facebook, including the Internet.org tie-up with Reliance Communcations, violate the principles of net neutrality.

The Telecom Regulatory Authority of India (TRAI) said it would review the free access arrangements, the Economic Times reported today. TRAI has called for public comments to develop a policy framework on net neutrality and internet-based messaging and calling services.

Many of the country’s mobile operators, including Idea Cellular, Uninor and Tata Teleservices, offer customers discounted access to social media apps such as Facebook and WhatsApp.

The response from TRAI comes just days after leading Indian e-commerce provider Flipkart decided not to get involved with Airtel’s sponsored data service called Zero, following protests from net neutrality supporters. Flipkart issued a statement saying Airtel’s service did not fit with its own values.

Airtel said it has been “stunned” by the decision and has strongly defended Zero as an open platform for app makers to provide toll-free data service which doesn’t violate the concept of net neutrality. Airtel continues to offer the controversial service.

Facebook chief Mark Zuckerberg this week rejected claims that Internet.org violates the concept of net neutrality.

A number of Indian companies have followed Flipkart’s move, with the Times Group, NDTV, Newshunt and Cleartrip reportedly announcing they will withdraw from Facebook’s Internet.org over net neutrality concerns. Internet.org is a Facebook-led initiative to provide data connectivity to two-thirds of the global population.

The zero-rating arrangements, which allow firms to subsidise users’ data charges to promote their apps and content, are now common across developing markets as well as a few developed countries. A year ago Facebook had deals with almost 20 operators in 14 countries.