A look at some recent key developments in the South China Sea, where China is pitted against smaller neighbors in territorial disputes over islands, coral reefs and lagoons in waters rich in fish and potential gas and oil reserves:
EDITOR'S NOTE: This is a weekly look at the latest key developments in the South China Sea, home to several territorial conflicts that have raised tensions in the region.
US RILES CHINA WITH 3RD SAIL-BY
A U.S. destroyer last week sailed by China's largest man-made island, the third freedom of navigation operation in seven months that challenges Beijing's vast claims in the South China Sea.
The USS William P. Lawrence made "innocent passage" within 12 nautical miles (22 kilometers) of Fiery Cross Reef, the limit of what international law regards as an island's territorial sea. The reef, which used to be submerged at high tide for all but two rocks, is now an artificial island with a long airstrip, harbor and burgeoning above-ground infrastructure. It dwarfs all other features in the disputed area, was recently visited by China's second-highest military officer and became prominent in the Chinese media when a famous singer of patriotic anthems entertained troops there recently.
China's Defense Ministry said it deployed two navy fighter jets, one early warning aircraft and three ships to track and warn off the vessel.
In response, it said that it will increase the scope of sea and air patrols and "boost all categories of military capacity building."
U.S. Assistant Secretary of State Daniel Russel said during a visit to Vietnam — which also claims Fiery Cross Reef, as does the Philippines — that the U.S. considers the area as international waters.
"If the world's most powerful navy cannot sail where international law permits, then what happens to the ships of smaller countries?" he told reporters.
The sail-by came as President Barack Obama prepares to visit Vietnam and Japan, the latter for a Group of Seven summit.
Chinese Foreign Ministry spokesman Lu Kang said that freedom of navigation should apply to commercial, not military ships. Such interpretation of international maritime law is controversial because the U.S. and most other nations consider innocent passage applicable to all vessels. It doesn't require prior notice, but also prohibits any hostile action or a stop by a ship unless it breaks down.
Critics in the U.S. Congress have demanded more assertive action from the Obama administration and called on the Navy to conduct helicopter flights and intelligence gathering within the territorial waters of China's man-made islands — a move that would sharply escalate tensions.
PENTAGON'S REPORT ON CHINA'S BUILDUP
The Pentagon released its most detailed report of China's island-building program. Some highlights:
— After reclaiming more than 3,200 acres (1,295 hectares) of land in the southeastern South China Sea, China's focus has shifted to developing and building military installations on man-made islands so it will have greater control over the region without resorting to armed conflict.
— The accelerated building effort doesn't give China any new territorial rights. But the airfields, ship facilities, surveillance and weapons equipment will allow China to significantly enhance its long-term presence in the South China Sea.
— China is using coercive tactics short of armed conflict, such as the use of law enforcement vessels to enforce maritime claims, to advance its interests in ways that are calculated to fall below the threshold of provoking conflict.
WILL NEW PHILIPPINE PRESIDENT CHANGE COURSE ON SOUTH CHINA SEA?
Rodrigo Duterte, the presumptive winner of the Philippine presidential election, says he wants to do things differently from his predecessor who has antagonized China, reopened military camps to U.S. troops and filed a U.N. court case challenging Beijing's claims in the South China Sea.
Duterte says he's open to talks with China on territorial conflicts, but also declares he will travel by a Jet Ski to one of the artificial islands that China has built and plant a Philippine flag there.
He says China should abide by an upcoming decision by the U.N. arbitration court, but he also asks why longtime allies America, Australia and Japan did nothing as Beijing built up the islands.
China apparently sees an opening.
According to Foreign Ministry spokesman Lu Kang, Beijing hopes the Philippines will "meet China halfway, taking concrete measures to properly deal with the disputes so as to put the ties of the two countries back on the track of sound development."
CHINA WON'T RECOGNIZE UN TRIBUNAL'S RULING
China is bracing for a possible unfavorable ruling by a U.N. arbitration court in The Hague in the next few weeks by publicly casting the process as biased.
Beijing has refused to take part in the proceedings, saying the U.N. has no jurisdiction in the case. That didn't stop the process, and even though the ruling is non-binding, it can damage Beijing's reputation and image if it refuses to heed it.
China says that at its core, the dispute is about sovereignty — who controls disputed features. China claims absolute sovereignty within its so-called "nine-dash line" that encompasses most of the sea.
The Philippines says China's claims are contrary to the U.N. Convention on the Law of the Sea. But it acknowledges that issues regarding sovereignty are not within the tribunal's jurisdiction and is not seeking a ruling on those claims. Instead, the Philippines wants the court to declare China's occupation of eight features reefs and outcroppings illegal and invalid.
Chinese diplomats have been busy briefing reporters and lobbying friendly nations to support Beijing's position that the tribunal has no jurisdiction and issues must be solved between China and other claimants individually.
"I must point out that relevant actions by the U.S. naval vessel threatened China's sovereignty and security interests, put the personnel and facilities on the islands and reefs at risk and endangered regional peace and stability." — Chinese Foreign Ministry spokesman Lu Kang.
Associated Press writers Hrvoje Hranjski in Bangkok, Christopher Bodeen in Beijing, Jim Gomez in Manila, Philippines, and Lolita C. Baldor in Washington contributed to this report.
Follow Hranjski on Twitter at www.twitter.com/hatbangkok
Gomez at www.twitter.com/JimSGomez