China has expressed strong indignation over the illegal intrusion by a United States warship into the Nansha Islands maritime area in the South China Sea. The US missile destroyer entered China's territorial waters near Yongshu Jiao on Tuesday without asking permission from the Chinese government.

Lu Kang, spokesperson of the Foreign Ministry of China, speaks at a press conference held in Beijing on May 10, 2016. [Photo: gov.cn]

"The relevant Chinese department took measures of monitoring, tracking and warning 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,"  Chinese foreign ministry spokesman Lu Kang said.

The Chinese foreign ministry spokesman made the comments at a daily briefing on Tuesday.  Lu also said that China had indisputable sovereignty over the Nansha Islands and its surrounding waters. He added that China has always fulfilled its obligations to maintain the freedom of navigation and flight over the region. The spokesman said there had never been any problem with the freedom of navigation and flight there.

"The United States had come out with the so-called 'Freedom of Navigation' scheme before the United Nations Convention on the Law of the Sea was signed in 1979. This is an obvious military challenge to the new marine order. It met with opposition from many countries and the United States has up to now refused to join the convention. It has actually placed its own interests above this convention. By flaunting the banner of freedom of navigation and flight, the United States has flexed its military muscles by sending warships and military planes close to and even into the related islands and reefs and their surrounding sea and air space for provocation. This is the biggest threat to the peace and stability and the freedom of navigation and flight on the South China Sea," Lu said.