Telecom tribunal TDSAT on Thursday reserved its judgement on Bharti airtel's plea against Rs 50- crore penalty imposed by the government for allegedly camouflaging the calling-line identification (CLI) while making promotional business calls to non-airtel customers.

A TDSAT bench headed by tribunal Chairman Justice S B Sinha asked many questions to airtel counsel on the issue during the 90-minute argument in the tribunal.

"...The Supreme Court has clearly told that if there is any masking (of the calls), then it is a violation," said Justice Sinha.

He also said it was not expected that airtel would not supply the CDR (Call Data Records) for verification of the facts to the Department of Telecom.

On airtel's submission that it was not done deliberately, the tribunal said, "It hardly matters that it was deliberate or not. Tampering is there."

The company said DoT passed the order imposing penalty without even giving a show-cause notice to the company.

Airtel said no show-cause notice was issued and it was still in dialouge with the Telecom Enforcement Resources & Monitoring Cell (TERM) while DoT imposed the penalty.

On this the tribunal said DoT was the licensor and only the licensor can impose penalty, not TERM.