Telecom Minister Kapil Sibal on Monday said that mobile phone subscribers will not have to pay roaming charges from next year.

"From next year. Our secretary has told you that it will be free from next year," Sibal said here in response to a query on the timing of removing roaming charges as proposed in the National Telecom Policy 2012.

The Minister was speaking to the media on the sidelines of the curtain raiser event of India Internet Governance Conference.

NTP 2012, approved in May, aims to abolish roaming charges and allow mobile phone subscribers to use same number across country without having to pay extra charges for services once they are outside their telecom circle.

Meanwhile, Telecom Secretary R Chandrashekhar said the Department of Telecom (DoT) is working on Notice Inviting Applications for spectrum auction after which it will work on unified licence (UL) guidelines - also a part of the NTP 2012.

"We are first going to attend to all issues linked to auction. The moment NIA is issued this week, we will focus on UL. After details of full UL is worked out, the modalities for free roaming will follow," he said.

As per the schedule, NIA will be issued on September 28.

GSM industry body COAI Director General Rajan S Mathews said he appreciated the concept of free roaming, but added that industry will have to work on details of implementation of 'One Nation - Free Roaming'.

When asked about the impact on mobile phone call rates, Mathews said, "That is matter which we will have to work with Trai (telecom regulator). Trai is ultimately responsible for setting the tariffs...We hope that Trai will follow due process of consultation paper."

He added that in a consultation paper, the Telecom Regulatory Authority of India will define what they expect and models they will use for determining tariff for nation wide free roaming.