China Unicom, the country's second-largest telecommunications operator, expects a big rise in its subscriber number after it launched the country's first official sales of iPhone 3GS late Friday.

Analysts on Saturday estimated the monthly rise to be 1.8 million this month, a sharp increase from 935,000 in September.

China Unicom started selling the iPhone 3GS in 285 Chinese cities on Saturday, hoping it will give an edge against its giant rival China Mobile, the world's biggest phone company by subscribers. Up until the end of September, China Unicom has 140 million subscribers, against China's Mobile's 500 million.