Defense Secretary Ash Carter said he will visit a U.S. aircraft carrier transiting the disputed South China Sea on Friday, a move bound to anger China, which has been increasingly asserting its territorial claims.
China claims almost the entire South China Sea, believed to have huge deposits of oil and gas. Brunei, Malaysia, the Philippines, Taiwan and Vietnam also have claims to parts of the waters, through which about $5 trillion in trade is shipped every year.
Carter, speaking at the close of joint U.S.-Philippines "Balikatan" military exercises in Manila, said he would visit the USS John C. Stennis, after visiting another carrier in the region in November.
"With each Balikatan and each cruise by the Stennis, with each new multilateral exercise and each new defense agreement, we add a stitch to the fabric of the region's security network," Carter said in prepared remarks. "This is the network - peaceful, principled, and inclusive - America continues to stand for, and stand with."
Though not unprecedented, it was still a visit likely to inflame tensions with China, which says the United States is "militarizing" the South China Sea and endangering security.
The United States has already conducted what it calls "freedom of navigation" patrols in the area, sailing within 12-nautical mile territorial limits around disputed islands controlled by China to underscore its right to navigate the seas.
Plans announced in Manila on Thursday to deepen U.S.-Philippine military ties, including joint patrols in the South China Sea, reflect a "Cold War mentality," China's Defence Ministry said, pledging to oppose any infringement on the country's sovereignty.
Carter said on Thursday the U.S. strategy was aimed at maintaining peace and lawful settlement of disputes, not provoking a conflict with a major world power.
"Countries that don't stand for those things, or don't stand with those things, are going to end up isolating themselves. But that will be self-isolation, not isolation by us," Carter said.
The carrier stop caps off a trip to Asia designed to highlight the expanding partnerships the United States is building with countries in the region, which Carter said had been asking for a greater U.S. role.
"We will continue to stand up for our safety and freedoms, for those of our friends and allies, and for the values, principles, and rules-based order that has benefited so many for so long," Carter said.
Hundreds of U.S. troops and some aircraft will stay behind in the Philippines temporarily, and on Thursday, the two countries revealed they had begun conducting joint patrols in the South China Sea.
Australian Prime Minister Malcolm Turnbull told reporters in Beijing that economic gains in Asia had been based on a "foundation of peace and stability" and were the engine room of growth for the whole world.
"So that is why, with respect to the South China Sea, we urge all claimants to settle territorial disputes peacefully and in accordance with international law."