China's foreign ministry has expressed concern after a U.S. navy warship carried out a navigation operation near a disputed reef in the South China Sea. Spokesman Lu Kang says the warship illegally entered Chinese territorial waters, and that the move threatened regional peace and stability. 

"The relevant Chinese department took measures to monitor, track and warn in accordance with the law. I have to point out, this action by the U.S. side threatened China's sovereignty and security interests, endangered the staff and facilities on the reef, and damaged regional peace and stability. As we have reiterated many times, China resolutely opposes this action by the U.S. side, and we will keep taking necessary measures to safeguard China's sovereignty and security," Lu said.

U.S. Defense Department spokesman Bill Urban said the guided missile destroyer "USS William P. Lawrence" travelled within 12 nautical miles of Chinese-Reef. Urban added that the operation was undertaken to challenge maritime claims by countries in the region. In response, China Foreign Ministry Spokesman Lu Kang said China firmly opposes such sea operations from the US, and endorses a two-track idea put forward by ASEAN countries to settle relevant disputes between nations.  

Lu also commented on water disputes with the Philippines, saying that China hoped the new government could meet China halfway to solve them.