Pentagon officials said two guided-missile destroyers had travelled within 12 nautical miles of Mischief Reef in the fiercely disputed Spratly Islands. The deployment is seen as the latest attempt by Washington to stand up to what it believes are attempts by Beijing to limit freedom of navigation in the strategic waters, where Chinese, Japanese and other Southeast Asian navies operate.
China claims almost all of the South China Sea and frequently criticises the US and its allies over naval operations near Chinese-occupied islands.
Britain today announced it was sending its new aircraft carrier HMS Queen Elizabeth to the volatile region on its first operational mission.
Beijing and Washington remain at loggerheads over US allegations for China’s militarisation of the South China Sea by building military installations on artificial islands and reefs.
China says the bases are essential for self-defense and accused the US of ramping up tensions in the region by sending battleships and warplanes close to the disputed islands.
Vietnam, the Philippines, Brunei, Malaysia, Indonesia and Taiwan all have competing claims for territory in the region.
The rising military tension comes against the backdrop of an increasingly bitter trade war between China and the US.
The two sides are trying to hammer out a deal ahead of a March 1 deadline when US tariffs on $200 billion worth of Chinese imports are scheduled to increase to 25 percent from 10 percent.
Escalating tensions between the United States and China have cost both countries billions of dollars and roiled global financial markets.
Observers fear the trade dispute is just one element in the deteriorating relationship between the world’s two top economies with top White House officials sharply criticising Beijing for everything from human rights abuses to cyber-warfare.
The two countries are also at odds over regional security, including Washington’s overtures to the self-ruled island of Taiwan, which China claims as its own.