A US Navy ship has sailed close to artificial islands built by China in the disputed waters of the South China Sea, US defence officials have said.

Guided-missile destroyer USS Lassen breached the 12-nautical mile zone China claims around Subi and Mischief reefs in the Spratly archipelago.

The freedom of navigation operation represents a serious challenge to China’s territorial claims.

The foreign ministry in Beijing condemned it as “illegal”.

In a statement, ministry spokesman Lu Kang described the operation as a “threat to China’s sovereignty”, adding that Beijing would “resolutely respond to any country’s deliberately provocative actions”.

US Defence Department spokesman Commander Bill Urban said earlier that “the United States is conducting routine operations in the South China Sea in accordance with international law”.