China begins operation of its sat-nav system

China says its domestically developed satellite navigation system has started global operation.

President Xi Jinping announced the completion of the BeiDou system at a ceremony on Friday.

The vice chairperson of the Communist Party's Central Military Commission, General Zhang Youxia, said China demonstrated the superiority of national unity and won a great victory by taking its own path.

The system was developed as a rival of the US-made Global Positioning System.

State-run media say BeiDou uses 45 satellites, the last of which was launched in June.

Data provided by the system reportedly have a margin of error of around 5 meters in the Asia-Pacific region. The government plans to expand the system's use by integrating it with 5G wireless technology.

The completion is likely to raise concerns among the United States and its allies, as Beijing is said to have developed the system for military purposes such as missile guidance.

China says BeiDou will be used by more than half of the world's countries.

Other nations including Japan and India are also working on new global navigation systems.