Tata Teleservices, Country's second-largest CDMA telecom operator, has decided to launch its GSM mobile services under the Tata DoCoMo brand, by end of this month.

Tata Teleservices, in which Japan's NTT DoCoMo has a 26% stake, has already invested close to $2 billion to roll out a pan-India GSM network.

A company executive, who did not want to be identified, has informed that the company intends to launch commercial services on the GSM platform in a phased manner, starting with South India, followed by western and northern regions

Currently, TTSL is India's sixth-largest mobile operator with 35.7 million subscribers as of end-April on the CDMA platform. Tata Teleservices is part of the INR 2,51,543 Crore (US$ 62.5 billion) Tata Group, that has over 87 companies, over 330,000 employees and more than 2.8 million shareholders.