The US military, whose shows of force in the Pacific have incensed Chinese leaders over the past year, will embrace a restrained response to a sweeping new ruling against Beijing's claims in the South China Sea, current and former officials said.

While US officials reject Beijing's attempts to assert its control over a vast swath of sea, they are equally eager to avoid confrontation with a rising military power that is a key commercial and financial actor.

"I would expect us to continue to do what we have been doing, which is calling for everybody involved in these disputes to work on solving them in a calm, rational order," a defence official said.

"And, yes, we've been pretty clear [about] the freedom to fly, sail and navigate in international waters and over international waters," the official said. "That was true before the ruling and will be true after."


The ruling from the Permanent Court of Arbitration in the Hague was seen as a victory for the Philippines, which brought the challenge, and other opponents of China's increasingly assertive posture in disputed areas.

It's not yet known what the ruling will mean for China's race to build up islands in contested areas, which include the construction of a runway, a port and satellite communication facilities.

Although China says its activities are defensive and backed by historic legal rights, the reclamation activities have raised alarm in countries across East Asia. Other nations, including Vietnam and Malaysia, also assert claims to areas that China contests.

In Washington, the Obama Administration reacted cautiously to the ruling, which China has warned it would not be bound by, but US officials said the court's findings should be respected.

White House press secretary Josh Earnest reminded reporters that the ruling was "final and binding," even though the court has little means to enforce its findings.

Dennis Blair, a former commander of US forces in the Pacific and director of national intelligence, said the Pentagon probably would continue what it calls its freedom of navigation operations, but it was unlikely to escalate those activities further, at least for now.

"I don't think this spirals into total war between China and the United States," Blair said. "I think [the Obama administration has] enough sense to give China the rhetorical and diplomatic space to back off the ledge that they've gotten onto."

Over the past year, the Pentagon has conducted a series of maneouvers around the contested Spratly and Paracel islands. In one incident, China scrambled fighter jets when the USS William P. Lawrence, a US guided-missile destroyer, sailed near Fiery Cross Reef. The US has also flown surveillance flights over disputed areas.


Beijing has responded angrily to such actions, accusing Washington of threatening Chinese territory and personnel.

Douglas Paal, a former White House and State Department official now at the Carnegie Endowment for International Peace, said the China appeared to be taking a similarly cautious approach for now. He said Beijing's response to the new ruling had so far been "calm and firm," in line with repeated rejections of the court's jurisdiction in recent weeks.

"They're not hitting the panic button," Paal said.

But Mira Rapp-Hooper, a scholar at the Centre for a New American Security, said that the Hague court's strong ruling in favour of the Philippines, which went beyond what most analysts had expected, increased the likelihood of a more threatening response from China.

"There will be particular worries that China may take destabilising moves, such as declaring an [air defence identification zone] or attempting land reclamation at a new location like Scarborough Shoal," she said.

An air defence identification zone, or ADIZ, over the South China Sea would require aircraft to coordinate with Chinese aviation authorities while flying over that area.


"Anything along these lines would be deeply problematic and serve to turn China's neighbours against it at an already tenuous time," Rapp-Hooper said.

Such actions could result in a more threatening response from the United States and its allies in the region.

The Pentagon is also likely to continue to build up its military presence with new and old Asian allies like the Philippines, an action that has antagonised Beijing.