RCom sent its letter to the Association of Unified Telecom Service Providers of India (AUSPI) to withdraw from the membership of the body recently, sources said.
The reason for the withdrawal of the Anil Ambani-led firm is not known. His elder brother Mukesh Amabni's telecom firm Reliance Jio is a member of another industry body Cellular Operators Association of India (COAI).
AUSPI officials could not be reached for comment, while RCom declined to speak on this.
This development leaves two core members -- Tata Teleservices and Sistema Shyam Teleservices (SSTL) in the industry body.
Considering that SSTL is in the process of merger with RCom, the latter's withdrawal from AUSPI pushes it into uncertainty.
AUSPI stood for telecom operators who started their business with CDMA technology and also vigorously defended dual licence policy whenever it came under attack from rival telecom sector body COAI.
It has two 'associate members' which include Chinese telecom gear maker Huawei and chipset maker Qualcomm.
Incidentally RCom was member of COAI but left it in 2007-08 after differences with incumbent telecom operators.
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