TTSL is a joint venture with Tata Group, in which Docomo invested in 2009, paying approximately $2.7 billion. Due to fierce competition the operator has struggled with heavy debts and falling market share in the Indian market for the last five years.
Tata Teleservices is 65% owned by Tata Group, while the remaining stakes are held by Docomo and foreign investment firms including an arm of Singapore state investment company Temasek Holdings.
The potential move would be one of many Japanese firms withdrawing from India's challenging market and follows Japanese drug firm Daiichi Sankyo’s deal to sell its stake in Ranbaxy Laboratories.
The news has stirred speculation that Vodafone is in discussions with the Tata Group to buy a majority stake in Tata Teleservices.
A deal with Vodafone could create India's largest mobile phone network, overtaking market leader Bharti Airtel.
