Apple's iPhone is scheduled to debut in China's mainland, the world's biggest mobile phone market, in three weeks in a partnership with China Unicom, the telecommunications carrier said yesterday.

The iPhone's official entry has been keenly anticipated and expected to increase competition in the smart phone market with rivals such as Nokia and Dopod, said Wu Wenzhao, a telecommunications analyst at Beijing-based IT research firm Analysys International.

China Unicom and Apple initially will kick off with two models: the iPhone 3G and the latest iPhone 3GS. The price will be lower than models bought on the black market, which cost 3,000 yuan (US$441) or more, according to a China Unicom source.

"The cooperation will open the door for Apple to enter the huge China market," said Sherrie Huang, an analyst at Ovum. "It also gives China Unicom a competitive weapon in the high-value subscriber segment."

An estimated 10 million mainland users already have iPhones, according to Ovum, a UK-based consultant.

China Unicom will start commercial use of 3G phones next month, its Shanghai branch said. Users will be able to buy iPhones through various packages from a starting price of about 100 yuan, Shanghai Unicom said.