A white Apple iPhone 4S is shown at an Apple Store in Clarendon, Virginia, October 14, 2011. [Photo/Agencies]

China Unicom is prepared to introduce the iPhone 4S and is only waiting for its network access certificate from authorities, said its sales executive Yu Yingtao, sina.com reported Wednesday.

As for when the iPhone 4S will be introduced, Yu said, "We will start sales once we get the certificate from the Ministry of Industry and Information Technology (MIIT). It's not up to us."

When China Unicom launched promotion of 3G smartphones, insiders assumed it as a signal that the company was giving up on iPhones. But Yu said, "We always consider iPhone the most strategic product, and we maintain a very good relationship with Apple."

Previous reports show that the iPhone 4S has passed all tests from MIIT and the network access certificate should be forthcoming. Some regional branches of China Unicom have started advance bookings for the iPhone 4S.