Defense Secretary Mark Esper has opposed what he called “aggressive behavior,” “destabilizing behavior” by China in Indo-Pacific and confirmed the U.S. commitment to the region.

At a press conference following the annual bilateral AUSMIN summit in Australia on Sunday, Aug. 4, the newly appointed Pentagon chief said the Indo-Pacific is a “priority theater” for the United States and warned China against predatory economic and other aggressive behavior in the region, the Weekend Australia reported.

“We firmly believe no one nation can or should dominate the Indo-Pacific,” Esper said. “We are working alongside our allies and partners to address the region’s pressing security needs.”

“We also stand firmly against a distribution pattern of aggressive behavior, destabilizing behavior, from China,” Esper said.

The U.S. defense secretary accused China of weaponizing the global commons, using predatory economics and “debt” for savage deals that promoted state-sponsored theft of other nation’s intellectual property.

“The U.S. will not stand idly by while any one nation attempts to reshape the region to its favor at the expense of others,” he said.

According to Reuters, the United States is challenging Chinese maritime hegemony and seeking to boost ties with nations pushing back against China after Beijing has triggered concerns within the region with its increasing assertiveness, especially in South China Sea.

U.S. Secretary of State Mike Pompeo on Friday slammed at China, saying its “decades of bad behavior” have hampered free trade and prompted tariffs from Washington.

On July 20, a State Department representative also called China’s action “bullying behavior” and expressed concern over reports that Beijing was interfering with oil and gas activities in the South China Sea, including Vietnam’s long-standing exploration and production activities.

In early July, a Chinese vessel accompanied by coast guard ships reportedly entered Vanguard Bank—the westernmost reef in the Spratly Islands—to conduct seismic research, prompting Vietnam to deploy its own coast guard vessels to the area in response.

The State Department in its statement said China’s repeated provocative actions threaten regional energy security and undermine the free and open Indo-Pacific energy market and asked China to cease its bullying behavior.