The Telecom Ministry's proposed new subscriber verification norms will slow down the pace of mobile customer addition by nearly 50 per cent to five million a month and will also drive up the cost for telcos to add users to their networks, feel operators.

"If the new norms are implemented, it will take at least 15 days for operators to activate a new mobile connection. The delay in the whole process may discourage new users... It is likely to half the subscriber addition from 10-12 million a month to 5 million a month," Cellular Operators' Association of India (COAI) Director General Rajan Mattews said.

On average, telecom operators add 10 to 12 million subscribers every month. In August, operators notched up 18.18 million new subscribers, taking the total number of mobile users in India to 670.60 million, as per the latest data from sectoral regulator TRAI.

The proposed new verification norms will also increase the cost for operators to register new subscribers, he added.

The DoT has proposed that telecom operators should send SIM cards to subscribers by registered post or through messengers on the rolls of the company, which will put an extra financial burden on the telcos, Mattews said.

The operators have been given time till Monday to give their suggestions on the proposed new norms.

A subscriber identity module (SIM) card securely stores data used to identify a subscriber on mobile telephony devices.

One of the leading telcos said, "The government is continuously putting law responsibility on operators... It is increasing our cost... We cannot play the law enforcement agency."

Earlier this month, the DoT had issued stringent subscriber re-verification norms, with many consumers using different networks across the country being temporarily or permanently disconnected.