U.S. destroyers have sailed close to Chinese reefs and islands in the disputed South China Sea in recent weeks, U.S. naval officials said on Thursday, patrols likely to fuel tensions ahead of landmark ruling over Beijing's maritime claims.
The destroyers Stethem, Spruance and Momsen have been patrolling near Chinese features in the Spratlys archipelago and the Scarborough Shoal, which is near the Philippines, the officials said. The patrols were first reported by the Washington-based Navy Times newspaper.
Pressure has been rising in the region ahead of a July 12 ruling by an arbitration court hearing the dispute between China and the Philippines over the South China Sea in the Dutch city of The Hague.
China has refused to participate in the case and vowed to ignore the rulings which the United States insists are binding and an important test of Beijing's willingness to adhere to international law.
While not close enough to be within 12 nautical miles - a so-called freedom of navigation operation that would require high level approval - the destroyers operated within 14 to 20 nautical miles of the Chinese features, the Navy Times reported.
The USS Ronald Reagan and its escort ships have also been patrolling the South China Sea since last week.
Pacific Fleet spokesman Lieutenant Clint Ramsden said he could not go into operational or tactical details but that the patrols were part of a "routine presence".
"All of these patrols are conducted in accordance with international law and all are consistent with routine Pacific Fleet presence throughout the Western Pacific."
U.S. navy officials said Chinese naval ships, and sometimes fishing vessels, frequently track U.S. ships in the South China Sea but it is not yet known if the presence of the destroyers attracted particular attention.
Manila is challenging the legality of Beijing's actions and claims in the South China Sea - the first legal case involving the South China Sea.
With legal experts expecting the ruling to go Manila's way, at least in part, U.S. and other regional naval officials are bracing for tension in the weeks and months after the ruling.