A US warship has sailed close to a disputed island in the South China Sea claimed by China.
The USS Stethem sailed within 12 nautical miles of Triton Island, which is part of the Paracel Islands.
The tiny island is also claimed by Vietnam and Taiwan.
China called the US move “a serious political and military provocation” and said it would take “all necessary means to defend national sovereignty and security”.
The so-called “freedom of navigation” operation happened just hours before US President Donald Trump was due to hold a pre-arranged phone call with his Chinese counterpart Xi Jinping.
This is the second such operation conducted during Mr Trump’s presidency. In May, the USS Dewey sailed less than 12 nautical miles from an artificial island built by China called Mischief Reef, which is part of the Spratly Islands.
US Defence Secretary James Mattis said a few days later that the US would not accept China’s militarisation of man-made islands in the region.
Rival countries have wrangled over territory in the South China Sea for centuries, but tension has steadily increased in recent years.
Its islets and waters are claimed in part or in whole by Taiwan, China, Vietnam, the Philippines, Malaysia and Brunei.
Beijing has been building artificial islands on reefs and carrying out naval patrols in waters also claimed by these other nations.
What is Freedom of Navigation?
- The US Freedom of Navigation programme challenges “excessive claims” to the world’s oceans and airspace
- It was developed to promote international adherence to the UN Convention on the Law of the Sea
- The US state department says the programme operates on a triple track; through “diplomatic representations, operational assertions by US military units…[and] bilateral and multilateral consultations with other governments”
- In the past years, the US conducted Freedom of Navigation operations against China, Malaysia, the Philippines, Taiwan, and Vietnam
The South China Sea dispute:
- Sovereignty over two largely uninhabited island chains, the Paracels and the Spratlys, is disputed by China, Vietnam, the Philippines, Taiwan and Malaysia
- China claims the largest portion of territory, saying its rights go back centuries – in 1947 it issued a map detailing its claims
- The area is a major shipping route, and a rich fishing ground, and is thought to have abundant oil and gas reserves
- The UN Convention on the Law of the Sea typically gives states an exclusive economic zone up to 200 nautical miles from their coastline – this would leave most of the Spratly Islands in the territorial waters of the Philippines and Malaysia