Mobile phones are a powerful tool for social transformation in India and the telecom industry needs to maintain affordable tariffs, but rates will have to be raised if operators are made to pay extra for the spectrum, Bharti group chief Sunil Mittal has said.

"We will favour affordable service which should be viable for industry. This has to be balanced," he told PTI at the Mobile World Congress here.

Against the backdrop of Indian telecoms passing through turbulent times, Mittal said it is a very powerful tool for social transformation and needs a balanced growth. "Who will gain if our business is shut down?".

About uncertainties over the pricing of spectrum, Mittal said, "We have been offering services with lower tariffs when we have not been charged for spectrum. Going ahead, if it (spectrum) will be charged, we will also have to charge the customer".

Of late, there has been a debate over the need to charge extra for the spectrum that has been allocated to incumbents like Bharti.

Last month, the Supreme Court cancelled 122 licences of new telecom operators in the 2G spectrum allocation case and asked the government to follow the auction of natural resources to avoid arbitrariness.

The Indian telecom sector has seen tremendous growth over the last few years, largely on the back of low tariffs that have fell further, triggered by the entry of new players.

In India, telecom tariffs are among the cheapest - even lower than seen in Africa.

"(Tariffs in India) are still best in the world. Rates in Africa are 7 cents which is Rs 3.5 per minute," Mittal said.

The industry is looking forward to the new National Telecom Policy, expected this year, for greater clarity on various issues including spectrum pricing.