China Unicom, the nation's only mobile operator offering Apple Inc's iPhone, released new rules to limit the resale of iPhones, Beijing News reported Monday.

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Unicom said that customers who buy iPhones from the carrier should use the smart phone with its bundled subscriber identity module card, or SIM card, or the operator will freeze the deposits and block the smart phone.

According to the old agreement, customers who buy the package from Unicom can get an iPhone and a bundled SIM card with some deposits, which would be released in 24 months.

However, in the gray market, some scalpers purchase the package and resell the phone and the card separately to earn more profits.

The new rules are targeted at the resale of iPhones and will be applied starting Dec 1.