China on Wednesday said it may declare an Air Defense Identification Zone (ADIZ) over disputed isles in the South China Sea, a day after an international court ruled against Beijing's sweeping territorial claims.
"The ADIZ is not a Chinese invention, but rather that of some big powers. If our security were threatened, of course we have the right. It depends on our comprehensive judgment," Vice Foreign Minister Liu Zhenmin said at a press conference.
The move would escalate tensions and be consistent with experts' warnings that China might increase its military presence in the South China Sea to show a tough stance on the issue.
Liu also urged other countries not to "take the opportunity to threaten China," referring to the Permanent Court of Arbitration in The Hague's judgment released on Tuesday.
The Philippines said Wednesday it would consult allies before taking the next steps, after the court ruled China has no legal rights in claiming a large swathe of the South China Sea.
President Rodrigo Duterte has instructed experts to study the 479-page decision, according to Defense Secretary Delfin Lorenzana.
China on Tuesday called the ruling "null and void" and reiterated it has historical rights to the South China Sea within a "nine-dash line" that covers almost 90 per cent of the area, which is a key shipping lane and rich in mineral and marine resources.
But the tribunal said "there was no legal basis for China to claim historic rights to resources within the sea areas falling within the nine-dash line."
It added that the Philippines has exclusive rights to the territories it claims in the South China Sea, because "those areas are not overlapped by any possible entitlement of China."
Manila filed the case in January 2013 after China took control of Scarborough Shoal, 124 nautical miles from the Philippines’ north-western coast.
The tribunal also ruled that China’s actions at Scarborough "violated the Philippines’ sovereign rights in its exclusive economic zone" by interfering with fishing and petroleum exploration conducted by Filipinos and constructing artificial islands.
Apart from China and the Philippines, Brunei, Malaysia, Taiwan and Vietnam also have overlapping claims to the South China Sea.