Partnership for cloud computing service

Alibaba Group Holding Ltd has teamed with its largest shareholder SoftBank Group Corp to form a cloud computing service venture targeting Japanese customers, as the Chinese e-commerce giant expands one of its fastest growing businesses.

The venture known as SB Cloud Corp will open a new data center in Japan to tap SoftBank's customers ranging from startups to global organizations, extending a battle for customers with Amazon.com Inc.

Alibaba will provide services including data storage and processing services, the companies said in a joint statement. Alibaba's cloud unit almost tripled revenue to more than 1 billion yuan ($153 million) in the March quarter. The business could account for more than $1 billion of Alibaba's revenue by 2018 and the public cloud presents a $120 billion global market opportunity, according to research by SunTrust Robinson Humphrey Inc.