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China Mobile reportedly has more than 1 million iPhones 5S handsets to offer its customers as its preps for the official launch on Friday.

Citing information from a "person familiar with the matter," The Wall Street Journal reported on Tuesday that Apple supplier Foxconn shipped 1.4 million phones to China's largest mobile carrier. Those phones are destined for new buyers and those who have preordered the 5S.

The number doesn't account for all of China Mobile's iPhone 5S sales earmarked for January, the Journal added, but it does provide some insight into early demand for the phone.

"Shipping 1 million or more iPhones to a single carrier per month is substantial," the unnamed source told the Journal. "But we have limited visibility beyond this month as Apple hasn't informed Foxconn of the volume for the next shipment to China Mobile."

Last month, China Mobile finally struck a deal with Apple to offer the iPhone to its 760 million subscribers. Smaller rival carriers China Unicom and China Telecom have been selling the two latest iPhones since they debuted last year. Both of those carriers also have trimmed contract prices on the iPhone to retain existing customers and lure new ones away from China Mobile.

For now, China Mobile has a leg up over its rivals with its new 4G network. However, China Unicom and China Telecom have both indicated plans to expand their networks to 4G as well. Last month, Piper Jaffray analyst Gene Munster predicted that Apple could sell as many as 17 million total iPhones via China Mobile this year, around 2 percent of the carrier's total subscriber base.

At the same time, the iPhone continues to face competition in China from Android vendors. Apple holds just 6 percent of the Chinese smartphone market, according to a November report from research firm Canalys, putting in it fifth place behind Samsung, Lenovo, and two Chinese companies.

"We have seen fading enthusiasm for iPhones compared with the past few years as we have more choices in China now," Gartner analyst Sandy Shen told the Journal. "There has been no dramatic change to the iPhone, and consumers want a larger screen size."