China Mobile, the world's biggest phone carrier by number of subscribers, says its latest quarterly profit declined 9.4 percent despite a rise in customer numbers as spending per account declined.

The state-owned carrier said Wednesday it earned 25.2 billion yuan ($4.2 billion) in the three months ending March 31. Total revenue rose 7.8 percent to 154.8 billion yuan ($25.8 billion) but revenue per user declined.

In a statement, the company said it experienced "severe challenges" due to the rapid evolution of mobile Internet and growing competitive pressure from other Chinese carriers.