U.S. President Barack Obama said Washington is concerned China is using its "sheer size and muscle" to push around smaller nations in the South China Sea, drawing a swift rebuke from Beijing which accused the United States of being the bully.
China's rapid reclamation around seven reefs in the Spratly archipelago of the South China Sea has alarmed other claimants, such as the Philippines and Vietnam, and drawn growing criticism from U.S. government officials and the military.
While the new islands will not overturn U.S. military superiority in the region, workers are building ports and fuel storage depots and possibly two airstrips that experts have said would allow Beijing to project power deep into the maritime heart of Southeast Asia.
"Where we get concerned with China is where it is not necessarily abiding by international norms and rules and is using its sheer size and muscle to force countries into subordinate positions," Obama told a town-hall event in Jamaica on Thursday ahead of a Caribbean summit in Panama.
"We think this can be solved diplomatically, but just because the Philippines or Vietnam are not as large as China doesn't mean that they can just be elbowed aside," he said.
Chinese Foreign Ministry spokeswoman Hua Chunying said the United States had no right to accuse anyone of pushing anyone else around.
"I think everyone can see very clearly who it is in the world who is using the greatest size and muscle," she told a daily news briefing in Beijing on Friday.
The United States needed to do more to show that it really wanted to play a constructive, responsible and positive role in the South China Sea, and should not ignore the efforts China and Southeast Asian nations have made to try and address the dispute, Hua added.