BEIJING/washington - Beijing "does not accept and does not recognise" the ruling by a UN-backed tribunal on its dispute with the Philippines over the South China Sea, the foreign ministry said Tuesday.

The declaration in a statement on its website followed a ruling by the Permanent Court of Arbitration in the Hague that China has no historic rights to its claimed "nine-dash line". "The award is null and void and has no binding force," the ministry said. "China neither accepts nor recognises it."

Beijing "does not accept any means of third party dispute settlement or any solution imposed on China," it added, reiterating its long-standing position on the dispute.

China has repeatedly denied the tribunal's authority to rule on the dispute with the Philippines over the strategically vital region, claiming that the court's actions are illegal and biased against it.

China, which boycotted the proceedings at the Permanent Court of Arbitration (PCA) in The Hague, rejected the ruling, calling it "null and void".

But analysts said it was a "huge win" for the Philippines, which brought the case. The resource-rich, strategically vital waters of the South China Sea are disputed between the Asian giant - which claims almost all of them on the basis of a "nine-dash line" that first appeared on Chinese maps in the 1940s - and several other countries including the Philippines. The row has embroiled the United States, which has deployed aircraft carriers and a host of other vessels to assert freedom of navigation in waters through which one-third of the global oil trade passes.

China says that its fishermen have visited the area for centuries, but the PCA tribunal said that under the UN Convention on the Law of the Sea (UNCLOS), Beijing had not had exclusive control of it.

Any historic rights were "extinguished" when it signed up to UNCLOS, it said, and there was "no legal basis for China to claim historic rights to resources within the sea areas falling within the 'nine-dash line'," it said.

Crucially, it ruled that none of the Spratlys, a chain of outcrops in the south of the sea, were "islands" under the meaning of UNCLOS, meaning that whoever had sovereignty over them - an issue it did not address - they were not entitled to 200-nautical-mile exclusive economic zones (EEZs) of their own.

The United States said on Tuesday that an arbitration court ruling that China has no historic title over the waters of the South China Sea should be treated as final and binding and not as a reason to raise tensions.

"We certainly would urge all parties not to use this as an opportunity to engage in escalatory or provocative action," White House spokesman Josh Earnest told reporters in a briefing aboard Air Force One.

Earlier, US State Department spokesman John Kirby termed the court's decision "an important contribution to the shared goal of a peaceful resolution to disputes in the South China Sea.""The United States expresses its hope and expectation that both parties will comply with their obligations," Kirby said.

Some sea areas were therefore definitely in the Philippines' EEZ, it said, as they were "not overlapped by any possible entitlement of China".

China had violated the Philippines' sovereign rights in its EEZ and the artificial islands Beijing has been furiously building in recent years - reshaping facts in the water in an effort to bolster its claim - have inflicted severe environmental damage, it added.

The damning decision was "as unfavourable to China as it can be", said Yanmei Xie, China analyst for the International Crisis Group.

The award by the five-member panel - chaired by a Ghanaian - "overwhelmingly favours the Philippines - a huge win," said M. Taylor Fravel of MIT.

Manila welcomed the decision but Beijing reacted furiously, saying it "neither accepts nor recognises" the ruling.

 "The award is null and void and has no binding force," China's foreign ministry said on its website, reiterating its territorial claims.

The official news agency Xinhua cited President Xi Jinping as saying the islands have been Chinese territory since ancient times, and Beijing will not accept any action based on the decision.

In Washington, the State Department said the ruling was an "important contribution" to resolving regional disputes and should be seen as "final and legally binding".

China is a permanent member of the UN Security Council and has been seeking a greater role on the global diplomatic stage, and will not want to be seen as a violator of international law.

But how the decision could be enforced remains open to question. Richard Heydarian, a political analyst at De La Salle University in Manila, told AFP: "China has been branded as an outlaw in unequivocal terms. US, Japan and other major powers should now focus on enforcing this binding verdict if China fails to comply."

In the short term, the decision was likely to escalate the "war of words" but would not immediately change the geopolitical dynamics in the sea, said Xie of the International Crisis Group.

"We're going to see a continuation of the chest thumping we've seen, especially from the China side."

Beijing has held naval drills between the Paracels and the southern Chinese island of Hainan in recent days, while US Pacific Command said on Twitter that the aircraft carrier USS Ronald Reagan had launched flight operations to support "security, stability" in the South China Sea.

Bonnie Glaser of the Centre for Strategic and International Studies told AFP: "I expect a very tough reaction from China since it has lost on almost every point."

China could choose to withdraw from UNCLOS, or begin building on Scarborough Shoal, which it seized from the Philippines in 2012 - which Washington would view as a provocation.

Beijing could also declare an air defence identification zone over the South China Sea, claiming the right to interrogate aircraft passing through the airspace, or try to remove a ship grounded by Manila on Second Thomas Shoal for use as a base.

Xu Tiebing, international relations professor at Communication University of China, told AFP that Chinese would see the PCA decision as evidence of international opposition to their country.

"These international organisations were not absolutely neutral, and in fact they are still subject to the manipulation and influence of big powers," he said.

The Philippines, which had lodged the suit in 2013, welcomed the "milestone decision", and foreign secretary Perfecto Yasay said: "We call on all those concerned to exercise restraint and sobriety."

Nationalist demonstrations are not rare in China, sometimes apparently with the tacit backing of authorities, and the Philippine embassy in Beijing has warned its citizens to beware of personal "threats". Chinese police sealed off the street where the mission stands.