A top U.S. Navy admiral said he joined a routine surveillance flight over the disputed South China Sea on Saturday, drawing a stern rebuke from China which said such activities seriously damaged mutual trust between the two countries.
Admiral Scott Swift, commander of the U.S. Pacific Fleet, confirmed at a press roundtable in Seoul on Monday that he had been aboard the seven-hour flight of a Boeing P-8 surveillance plane, but gave no specific details about the flight.
In May, Beijing called a P-8 surveillance flight carrying a CNN team over the South China Sea "irresponsible and dangerous".
Swift said his flight was routine, like the earlier CNN flight, and did not say if China responded to Saturday's patrol.
"We have forces deployed throughout the region to demonstrate the United States commitment to freedom of navigation," said Swift, adding the flight allowed him to see "first-hand" new operational capabilities in the fleet.
Swift said communications with China at sea were "positive and structured". "They're normalized, if you will," he said.
China's Defense Ministry said it hoped the U.S. did not choose sides in the dispute, and that it was "resolutely opposed" to U.S. surveillance flights, though did not say if it warned his aircraft away.
"For a long time, U.S. military ships and aircraft have carried out frequent, widespread, close-in surveillance of China, seriously harming bilateral mutual trust and China's security interests which could easily cause an accident at sea or in the air," the ministry said in a statement sent to Reuters.
In a separate statement, China's Maritime Safety Administration warned ships not to enter waters to the east and southeast of Hainan island from July 22 to July 31 due to military exercises. It gave no other details.
Chinese dredging vessels are purportedly seen in the waters around Mischief Reef in the disputed Spratly Islands in this still image from video taken by a P-8A Poseidon surveillance aircraft provided by the United States Navy May 21, 2015.
China has almost finished building a 3,000-metre-long (10,000-foot) airstrip on one of its artificial islands in the disputed Spratly archipelago of the South China Sea, according to satellite imagery of the area.
Beijing claims most of the South China Sea, with the Philippines, Vietnam, Malaysia and others holding overlapping claims.
Washington has demanded China halt land reclamation and militarization of the disputed area and to pursue a peaceful resolution according to international law.
China stepped up its creation of artificial islands last year, alarming several countries in Asia and drawing criticism from Washington.
Beijing says the outposts will have undefined military purposes, as well as help with maritime search and rescue, disaster relief and navigation.
"There are forces of instability at play in the region, and that's generating uncertainty," said Swift, without giving details.
"I wish I had a crystal ball that I look into the future and see. I am concerned about the forces of destabilization that appear to be more current here in the theater," he said.
"And that's what I hear from my friends in the region as I communicate with them ... The lack of certainty - the growing uncertainty of those countries in the region".