China has rejected U.S. accusations that it is using vague territorial claims unsupported by international law to gradually take control of areas in the disputed South China Sea.
Chinese Foreign Ministry spokesman Hong Lei issued a statement late Saturday calling on the U.S. to take a "rational and fair attitude" in the dispute.
China claims nearly the entire 3.5 million square kilometer South China Sea by virtue of what it sees as its historical rights within the so-called nine-dash line. Vietnam, the Philippines, Taiwan, Malaysia and Brunei also claim parts of the region.
In congressional testimony Wednesday, U.S. Assistant Secretary of State for East Asian and Pacific Affairs Danny Russel said any use of the nine-dash line to claim maritime rights must be based on land features, such as a nation's coastline or its islands. He urged Beijing to clarify or adjust its claims to bring them into accordance with international law of the sea.
Russel said there were "growing concerns" that China is trying to gradually assert control over the area, despite objections by its neighbors. He cited several Chinese actions that recently have "raised tensions," including continued restrictions on access to the Scarborough reef, pressure on the longstanding Philippine presence at the Second Thomas Shoal and the recent updating of fishing regulations covering disputed areas in the South China Sea.
Russel also raised fresh U.S. concerns over China's activities in the East China Sea, where Beijing recently set up an Air Defense Identification Zone in an area also claimed by Japan.
He called the move a "step in the wrong direction," and warned China against setting up ADIZs elsewhere.