NEW DELHI: The Department of Telecom has moved the Supreme Court challenging tribunal TDSAT's judgment that allowed Airtel, Idea and Vodafone to offer 3G services under a roaming arrangement in areas where not all of them own 3G spectrum.

"Legal opinion has favoured challenging TDSAT judgement dated 29 April on 3G intra-circle roaming. DoT has sent petition to Supreme Court registry around a week ago for appeal against the judgement," an official source told.

The Telecom Disputes Settlement and Appellate Tribunal had overturned a government ban on offering 3G mobile services beyond their licensed zones through roaming pacts, saying that it was in national interest to allow better utilisation of scarce radio frequency.

The three operators - Airtel, Vodafone and Idea Cellular – benefitted from this judgment as they were facing a penalty of Rs 1,200 crore for entering into pacts with each other to offer 3G services in regions where they did not win spectrum in the 2010 auction.

Airtel had won the 3G spectrum in 13 out of 22 telecom service areas for Rs 12,295.46; Vodafone in 9 for Rs 11,617.86 and Idea Cellular in 11 circles for Rs 5,768.59 crore.

DoT issued notices to Airtel, Vodafone and Idea on 23 December 2011 asking them to stop 3G ICR within 24 hours and report compliance but the order was challenged by them.

Tata Teleservices and Aircel too had signed 3G ICR but immediately called off their agreement after DoT issued notice to them.

Following the TDSAT judgement, Airtel, Vodafone and Idea have extended service under their 3G ICR at pan-India level except Odisha.

Reliance Communications also entered in similar agreement with Tata Teleservices to provide 3G services in Karnataka, Andhra Pradesh, Tamil Nadu, Kerala and UP-East telecom Circles.