By Sunil Raman
BBC News, Delhi
Indian cellular phone companies and phone users have welcomed a government move to curb unsolicited calls and text messages from tele-marketers.
Millions of new mobile users are added in India every month
The Telecom Regulatory Authority of India said on Tuesday that in three months time subscribers would be able to register on a "do not call" list.
Firms breaking the rules face a fine of 500 rupees ($13) for each call or text.
India has the fastest growing mobile phone market in the world, with more than 170 million subscribers.
Every month around seven million new subscribers are added to the list.
The telecom regulator estimates that about 10 billion unsolicited calls are made annually.
'Violation of rights'
Anand Chintamani, marketing head of an IT consulting company, said he was very pleased at the announcement and called it "long overdue".
Call centres are booming in India
"I was in South Africa a few months ago on work and got a call at 5am from someone in India who wanted to sell me a washing machine!" he told the BBC.
"I flew into a rage and lodged a complaint on my return to Delhi. But I still get unsolicited calls from credit card companies, banks and hotels."
Millions like Mr Chintamani have been harassed by calls from people trying to sell everything from credit cards to cheap house loans and even music systems.
Complaints filed with service providers met with little response until someone went to the Supreme Court alleging cold-calling was a "violation of his fundamental rights".
The announcement from the Telecom Regulatory Authority of India (Trai) came after an order from the Supreme Court.
Trai said it would set up a "Do Not Call Registry" along similar lines to one adopted by the United States in 2003.
Subscribers who do not want to receive unsolicited calls will be able to add their name to the list.
Service providers are often accused of selling personal data of mobile users to tele-marketing companies.
Under the new regulation, the government-run National Informatics Centre will prepare a data base for the national "Do Not Call Registry" within three months and all tele-marketers will need to get themselves registered.
Any call or text message sent to a person whose number is on the list will be penalised.
A fine of 500 rupees will be charged for every unsolicited call made. Tele-marketers who offend with the same person three times will face being disconnected.
The head of the Cellphone Operators' Association, TV Ramachandran, welcomed the curbs, but said no one should believe that unsolicited calls would stop completely.
"It is an excellent move, we have all been victims of unsolicited calls. It has a good chance of being reasonably successful," he said.
But Mr Ramachandran added: "Call centre people will have to be better trained, tele-marketing operations have to be professionalised. You can never have a fool-proof system."
MC Chaubey, an adviser at Trai, is more optimistic. He says the penalty will act as a deterrent for tele-marketing companies even if it does not solve the problem completely.