Conexus Mobile Alliance, a group of Asian mobile operators including Japan's NTT DoCoMo Inc. (9437.TO) and South Korea's KT Corp. (030200.SE), is likely to unveil later Tuesday a partnership with Vodafone Group PLC (VOD.LN), people familiar with the situation said.

Conexus' partnership with Vodafone, the world's largest mobile operator by revenue, includes collaboration on mobile services, the people said, without giving further details.

The move comes after Singapore's M1 Ltd. (B2F.SG) and Hong Kong's SmarTone Telecommunications Holdings Ltd. (0315.HK), members of rival alliance Asia Mobility Initiative, separately said Monday they won't renew their respective partnerships with Vodafone when they expire this year.

Vodafone wasn't immediately available for comment.

Conexus comprises NTT DoCoMo, KT Corp., Hutchison Telecommunications Hong Kong Holdings Ltd. (0215.HK), India's Bharat Sanchar Nigam Ltd. and Mahanagar Telephone Nigam Ltd. (500108.BY), Indonesia's Indosat (ISAT.JK), Philippines' Smart Communications Inc., Singapore's Starhub Ltd. (CC3.SG), Taiwan's Far EasTone Telecommunications Co. Ltd. (4904.TW), Thailand's TrueMove, and Vietnam's VinaPhone.

According to Conexus' website, the alliance has a combined customer base of about 310 million mobile subscribers.

-By Chun Han Wong, Dow Jones Newswires; +65 64154 160; chunhan.wong@dowjones.com