China accused the United States on Thursday of threatening to sow "chaos" in the Asia-Pacific region by inciting countries whose territorial claims in the South China Sea clash with those of Beijing.

It is the latest round in a war of words over the area, where tensions are mounting and rhetoric escalating.

China is rapidly building artificial islands in the disputed waters, and US Defense Secretary Ashton Carter on Wednesday demanded an "immediate and lasting halt to land reclamation by any claimant".

Beijing's foreign ministry spokeswoman Hua Chunying told a regular briefing: "If the major powerhouse of world economic growth is thrown into chaos, will that serve the interests of the American side?"

The countries that make up the Asia-Pacific Economic Cooperation forum account for more than 50 percent of global GDP and nearly half of world trade.

The South China Sea is a major shipping route for international trade.

Beijing insists it has sovereignty over nearly all of the South China Sea, including waters far from the Chinese mainland and near the coasts of the Philippines, Vietnam and other Asian neighbours.

The Chinese military last week ordered a US Navy P-8 Poseidon surveillance plane to leave an area above the disputed Spratly islands. But the American aircraft ignored the demand and said it was flying in what US officials consider international airspace.

Hua told Washington to "refrain from all the provocative words and deeds".

"A few countries keep stirring up troubles in the South China Sea for (their) own selfish gains and provoking China's territorial sovereignty and maritime rights and interests, while there are some other people who incite them to do so," she added.

Carter made his remarks in Hawaii as he prepared to embark on an Asian tour.

"First, we want a peaceful resolution of all disputes and an immediate and lasting halt to land reclamation by any claimant," he said, according to remarks posted on the Department of Defense website.

"We also oppose any further militarisation of disputed features."

It is his second tour of the region since taking over at the Pentagon in February and his itinerary includes Singapore, Vietnam and India.

Beijing has expanded its land reclamation work in the South China Sea at a dramatic pace in recent months, constructing man-made islands on top of reefs across a wide area to back up its territorial claims.

Several other claimants have already built airstrips in the region and Hua accused the US of being "selectively mute" regarding what she said were construction activities carried out on "illegally occupied" Chinese territory.

"I'd like to reiterate that the scale and speed of China's construction work is commensurate with the international obligation of China as a major country," she said.

"It is for the Chinese people themselves to decide what to do. No one else has the right to tell China what should be done."