South China Sea: US and China have escalating war of words over territory dispute

Top US Navy commander calls for fresh patrols in the region

China has been building artificial islands in the disputed South China Sea. File photo (Getty Images)

The world's two most powerful countries are involved in an escalating dispute over territory in the South China Sea.

China has nearly finishing developing artificial islands in an area the US-allied Philippines has also claimed, and it's feared that they will be used as military and naval bases to intimidate other countries and dominate the oil-rich region — which also happens to be one of the world's most important commercial waterways.

China says it has sovereignty over the Spratly Islands, and there's no hostile intent. Vietnam, Malaysia, Taiwan and Brunei also have claims in the South China Sea.

US Navy Admiral Harry Harris told the Senate China's militarisation in the region is of "great concern" and pressed for patrols close to "those islands that are not islands."

Republican Senators, including John McCain, told the Pentagon to take actions that challenge China's claim to the territory.

The Chinese Foreign Ministry said it was "extremely concerned" by the comments, and that China was against "any country challenging China's sovereignty and security in the name of protecting freedom of navigation".

"We demand that the relevant country speak and act cautiously, earnestly respect China's sovereignty and security interests, and not take any risky or provocative acts."

Citing recent satellite footage, US expert Bonnie Glaser has said China is continuing to reclaim land in the region despite saying it stopped more than a month ago.

This heated war of words has kicked off just before Chinese President Xi Jinping visits the United States for a week. It's thought that President Barack Obama will want to talk about what's happening in South China Sea.