A top military officer has made a rare visit to some of the islands in the South China Sea amid rising maritime tension caused by a recent US-Philippine joint patrol.

Vice-Chairman of the Central Military Commission Fan Changlong made the visit "in recent days" to China's Nansha Islands, according to a statement released by the Defense Ministry on Friday.

The commission, China's top military commanding agency with two vice-chairmen including Fan, is headed by President Xi Jinping.