By Caleb Stephen, Australia and Asia-Pacific Reporter

SYDNEY, AUSTRALIA (WeAreChange)  — A United States Admiral has declared his country is “ready to confront” Beijing in the South China Sea over ongoing disputed island claims that threaten to escalate tensions between the two global rivals.

China claims most of the resource-rich South China Sea through which about $5 trillion in ship-borne trade passes every year. Neighbours Brunei, Malaysia, the Philippines, Taiwan and Vietnam also have claims in the vast expanse of ocean.

Earlier this year, the U.S. called upon China to respect the findings of an arbitration court in The Hague which invalidated its vast territorial claims in the strategic waterway.

But Beijing continues to act in an “aggressive” manner, to which the United States stands ready to respond, Admiral Harry Harris, head of the U.S. Pacific Command, said in a speech in Sydney on Wednesday.

“We will not allow a shared domain to be closed down unilaterally no matter how many bases are built on artificial features in the South China Sea,” he said.

“We will cooperate when we can but we will be ready to confront when we must.”

Harris’ comments further exacerbate the already tense situation between Beijing and U.S. President-elect Donald Trump who broke diplomatic protocol by accepting a telephone call from Taiwan’s president on Dec. 2 – a move that prompted a diplomatic protest from Beijing.

The United States estimates Beijing has added more than 3,200 acres (1,300 hectares) of land through dredging operations in the South China Sea over the past three years, building runways, ports, aircraft hangars and communications infrastructure.

Artificial Chinese controlled islands in the disputed South China Sea

Artificial Chinese controlled islands in the disputed South China Sea

In response, the United States has conducted a series of freedom-of-navigation operations in the disputed waters, the latest of which occurred in October.

The patrols have continually infuriated Beijing, with one senior Chinese official in July warning the practice may end in “disaster”.

Harris said the United States would continue with its practice of patrolling the waters but said it was a decision for its ally, the Australian government, as to whether they should undertake their own freedom-of-navigation operations.

“The U.S. fought its first war following our independence to ensure freedom of navigation,” said Harris. “This is an enduring principle and one of the reasons our forces stand ready to fight tonight.”