United States military officials claimed on Monday that a Chinese warship harassed an American Navy vessel in the South China Sea. The USS Decatur passed within 12 nautical miles of two reefs in the Spratly Islands, on a “freedom of navigation” mission on Sunday, CBS News reported. Beijing considers this Chinese territory.

US Navy Commander Nat Christensen said that the Chinese warship came within 45 yards of the American vessel, BBC reported. The Luyang destroyer forced the USS Decatur off course, in an “unsafe and unprofessional manner,” the American Navy said.

Monday’s incident too was condemned by the Chinese. “The US side repeatedly sends military ships without permission into seas close to South China Seas islands, seriously threatening China’s sovereignty and security, seriously damaging Sino-US military ties and seriously harming regional peace and stability,” the Chinese Defence Ministry said.

In June, US Secretary of Defense James Mattis had accused Beijing of “intimidation and coercion” in the South China Sea. In May, the United States had disinvited China from participating in annual maritime exercises in the Pacific in protest against Beijing’s militarisation of the South China Sea.

South China Sea dispute

China and several neighbouring countries make competing claims to parts of the area. Taiwan, the Philippines, Brunei, Malaysia and Vietnam all make claims to parts of the South China Sea. Beijing claims a huge area known as the “nine-dash line”, and routinely accuses the US Navy of provocation.

In July 2016, an international tribunal in The Hague ruled in favour of the Philippines and said Beijing has no legal basis to claim “historic rights” over the South China Sea. The Permanent Court of Arbitration accused China of breaching the sovereign rights of the Philippines