Two Chinese civilian aircraft have landed at two new airports on reefs controlled by China in the South China Sea a day after a tribunal in The Hague denied Beijing's claims to the energy-rich waters.
The aircraft touched down on Mischief Reef and Subi Reef in the Spratly Islands on Wednesday before returning to the southern Chinese island province of Hainan from where they had taken off, the official Xinhua news agency said.
China also said it has the right to set up an air defense zone in the area as it pledged to take all necessary measures to protect its sovereignty over the South China Sea.
Chinese Vice Foreign Minister Liu Zhenmin said Beijing could declare an air defense identification zone over the waters if it felt threatened.
"We hope that other countries will not take this opportunity to threaten China and work with China to protect the peace and stability of the South China Sea, and not let it become the origin of a war."
China's ambassador to the US blamed the rise in tension in the region on the United States' "pivot" toward Asia in the past few years.
The tribunal in The Hague, Netherlands, on Tuesday rejected China's claims to the islands, which overlap in parts with Vietnam, the Philippines, Malaysia, Brunei and Taiwan.
China's Vice Foreign Minister Liu Zhenmin took aim at the judges on the tribunal, saying that as not one of them was Asian they could not possibly understand the issue and it was unfair of them to try.
China's Ambassador to the US Cui Tiankai said the arbitration case "will probably open the door of abusing arbitration procedures."
In a front page commentary, the ruling Communist Party's official People's Daily said, "China will take all necessary measures to protect its territorial sovereignty and maritime rights and interests."
The South China Sea waters are believed to sit atop vast reserves of oil and gas. The dispute has at times drawn in trans-regional countries, particularly the US.
Beijing accuses Washington of meddling in regional issues and deliberately stirring up tensions in the South China Sea.
The US, in turn, accuses China of carrying out what it calls a land reclamation program in the South China Sea by building artificial islands in the disputed areas.