Indian telco Bharti Airtel has clashed with Tata-owned Tejas Networks over claims that the latter's network equipment has caused interference issues in Rajasthan.

The Economic Times reported this week that Airtel has called Tejas' equipment, which has been deployed by state-run Bharat Sanchar Nigam Ltd (BSNL), "sub-standard."

The publication reports that Tejas blamed telco giant Airtel for putting up sites very close to BSNL, which was leading to interference in the Rajasthan region.

Airtel has hit back at Tejas Networks, arguing that the issue is with Tejas' equipment.

"The claim made by Tejas Networks is baseless. Towers have historically accommodated two or more sites of different operators without interference, so the problem isn't due to the closeness of sites. The current problem is more a function of sub-standard equipment which doesn't conform to Indian spectrum allocation requirements," said Airtel in a statement to ET.

Airtel wrote to Tejas on November 14, noting the issue around interference and informing Tejas that it was being caused by the equipment deployed by BSNL, asking for the company to take immediate action.

The issue itself, Airtel alleges, is due to technical non-conformance in Tejas' radio equipment and filter design. Airtel said that the filter supplied by Tejas was designed for the 800 MHz band within the frequency range of 864-894 MHz, aligned with certain international standards.

This is an issue, however, as in India, the 800 MHz downlink operates strictly between 869 to 889 MHz, Airtel said.

Tejas rejected the claims made by Airtel and has instead blamed the telco.

"The interference from BSNL to Airtel arises not due to Tejas's radios not meeting out-of-band emission specifications but primarily because Airtel's sites are deployed very close to BSNL's, without adequately maximizing coupling losses," said Tejas in response to Airtel.

Tejas previously confirmed it received a $900 million purchase order from state-owned telco Bharat Sanchar Nigam Limited (BSNL) to supply equipment for BSNL's 4G and 5G rollout.