Updated: 03/07/17 : 06:20:31Printable Version
Beijing has called the presence of a US warship near a disputed island in the South China Sea "a serious political and military provocation".
The USS Stethem sailed within the territorial limits of Triton Island, part of the Paracel Islands, claimed by China and others.
China responded by sending ships and fighter jets to the island.
It happened hours before US President Donald Trump and Chinese counterpart Xi Jinping spoke on the phone.
But a White House statement about their call did not say if they had discussed the incident.
The US has repeatedly warned China against its occupation and aggressive reclamation of islands in disputed waters, but Beijing says it is within its sovereign rights to do so.
Mr Trump and Mr Xi instead "reaffirmed their commitment to a denuclearised Korean peninsula", the White House said. Mr Trump also discussed North Korea with Japan's Prime Minister Shinzo Abe in a separate call.
In a statement late on Sunday, China's foreign ministry confirmed reports that the USS Stethem had entered waters claimed by China.
The warship had sailed within 12 nautical miles of Triton Island as part of its "freedom of navigation" operations, according to news agencies and Fox News citing US defence officials.
UN rules dictate that any territory can claim the waters up to 12 nautical miles from its coast. The sailing of a US ship within those limits indicates the US does not recognise those territorial claims.
Beijing said it would use "all necessary means to defend national sovereignty and security".
It also accused the US of "deliberately stirring up troubles" in the region as China and Southeast Asian neighbours have "cooled down and improved the situation".
The tiny island is also claimed by Vietnam and Taiwan. China has been embroiled in maritime disputes with several of its regional neighbours in recent years.