Apple has partnered with the Guizhou-Cloud Big Data firm for this project.
Previously, Chinese customers' iCloud data have been stored in Apple's overseas data centers.
The terms include a clause that Apple and the Chinese company "will have access to all data that you store on this service, including the right to share, exchange and disclose all user data, including content, to and between each other under applicable law". The Communist Party mouthpiece also said Apple was to begin sending notifications of the change to users Wednesday.
iCloud data will be transferred from 28 February, Apple said. Yet Apple still announced last July that it would invest $ 1 billion in Guizhou so as to establish the new database there.
"Have you often experienced slow access speed and freezes when you sync your iPhone photos, videos, documents and apps to iCloud?" it wrote on its official Weibo account.
That followed Apple's announcement in July a year ago of a partnership with GCBD to establish its first data centre in China, which forms part of the U.S. technology company's US$1 billion investment programme in Guizhou.More news: Margot Robbie and Chris Hemsworth hilariously battle to be the 'Best Aussie'
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Another industry policy issued by the Ministry of Industry and Information Technology in January 2017 stipulates cloud services in China must be operated by Chinese companies and foreign firms must partner with qualified domestic players to launch such services. Apple has now confirmed that the switchover will take place in February. Those who aren't happy with the move at least have the option of closing their iCloud accounts.
In a statement to the website 9to5mac, Apple said it remained committed to "transparency" in its Chinese operations.
Apple sent out a message to customers in China this week, revealing terms and conditions of the changeover. These facilities are used by companies to remotely store large amounts of data and host cloud computing services, which enable users to buy, lease or sell software and other digital resources online on demand, just like electricity from a power grid.
Apple announced the new data base in Guizhou last July, with an investment of 1 billion USA dollars.
Read into it what you will, but the ties between Apple and the Chinese government are strengthening.