As usual, the Obama administration is talking tough on foreign policy. Defense Secretary Ashton Carter warned China on Wednesday to stop building man-made islands in the South China Sea so that the Communist country can expand its territorial zone.

“There should be no mistake: the United States will fly, sail, and operate wherever international law allows, as we do all around the world,” said Carter.

The South China Sea is used by numerous countries for shipping lanes, and to date, China claims ownership of 80 percent of the area.

Last week, a U.S. Navy Poseidon P-8A surveillance aircraft flying near the disputed Spratly Islands ignored eight Chinese orders to leave; China has been expanding a reef there into an artificial island. China’s Foreign Ministry called the refusal to leave “very irresponsible and also dangerous,” but the Pentagon insisted the area was still in international airspace.

“China is out of step with both international norms that underscore the Asia-Pacific’s security architecture, and the regional consensus in favor of non-coercive approaches to this and other long-standing disputes,” Carter said. “China’s actions are bringing countries in the region together in new ways… And they’re increasing demand for American engagement in the Asia-Pacific. We’re going to meet it. We will remain the principal security power in the Asia-Pacific for decades to come.”

Carter spoke in Hawaii at a ceremony honoring Admiral Harry B. Harris as the new commander of U.S. forces in the Pacific. He is scheduled to speak in Singapore about the tensions between the U.S. and China. Another speech is scheduled for Vietnam, which also claims sovereignty in the South China Sea.