State-owned MTNL has invited bids from operators, who could not get 3G spectrum in Delhi and Mumbai in the auction held last month, for providing roaming facility to their 3G subscribers in the PSU's network.

This gives a business opportunity of earning up to Rs 300 crore revenue annually to the PSU, significant to make its 3G operations commercially viable, MTNL CMD Kuldeep Singh said.

No operator other than Bharti, Vodafone and Reliance Communication could succeed in getting 3G spectrum in Delhi and Mumbai in the auction held recently. Both MTNL and BSNL were given 3G spectrum nearly a year ahead of others.

While others, who have managed to get 3G spectrum in the rest of the circles but for these two metros, cannot make their operations viable without having services in these two key circles.

"We are looking at huge business opportunity in this and have invited bids from two operators, to begin with, each in Delhi and Mumbai to tie up for one-way roaming. We are asking for fixed cost as well as network usage charges," Singh told PTI.

MTNL need not go for two-way roaming as it enjoys exclusive roaming agreement with its big brother BSNL throughout the country.

MTNL has taken over Rs 7,000 crore debts to pay for spectrum for both 3G and Broadband Wireless Acess (BWA) and it would be difficult for the PSU to service huge loans without making its operations profitable.

"We have to make judicious use of the spectrum available to us and this is one of the revenue streams (tying up with operators who did not get 3G spectrum in Delhi and Mumbai) available to us," MTNL Chief said.

The PSU has kept the minimum cost at Rs 70 crore per operator per metro. Of this Rs 50 crore would be fixed charges annally and Rs 20 crore would be for using the network for which the operator would be offered discount.

Over usage of network would entail more revenues for both as it would be shared between the two.

An Expression of Interest (EoI) has been floated to provide an opportunity to roam in MTNL 3G network as per terms and conditions mentioned for the customers of telecom providers not having 3G spectrum in Delhi and Mumbai areas.