The United States will conduct freedom of navigation operations in the South China Sea again.
The announcement was made by US Defence Secretary Ash Carter on Saturday, 7 November, although he gave no timeline for any such actions.
Carter's comments, delivered at a defence forum at the Ronald Reagan Presidential Library in California, came at the close of a trip to Asia, where he cruised on a US aircraft carrier operating in the South China Sea, and blamed Beijing's island-building for rising tensions in the region.
In October, a US guided-missile destroyer, the "USS Lassen", challenged territorial limits around one of China's man-made islands in the Spratly archipelago with a so-called freedom-of-navigation patrol.
"We've done them before, all over the world," said Carter, in reference to the operation. "And we will do them again."
A rising and more ambitious China and Russia intent on flouting the international order means the US military must adapt certain strategies and operations, said Carter.
"How China behaves will be the true test of its commitment to peace and security," he added. "This is why nations across the region are watching China's actions in areas like the maritime domain and cyberspace."
China claims most of the South China Sea, through which more than $5 trillion in global trade passes every year. Vietnam, Malaysia, Brunei, the Philippines and Taiwan have rival claims.
"China has reclaimed more land than any other country in the entire history of the region," said Carter.
The United States is "deeply concerned" about the extent of land reclamation and the prospect of further militarisation there, which could lead to a greater "risk of miscalculation or conflict", he said.
The United States is responding to China's moves by putting its "best and newest" assets in the Asia-Pacific and investing in space, cyber, missile defence and electronic warfare, he added.
