Explainer | South China Sea: the dispute that could start a military conflict
- China is just one of a number of countries to claim sovereignty over part of the maritime area, which is believed to harbour a wealth of oil and natural gas reserves
- The sea is the focus of intense military interest, with Beijing establishing outposts on artificial islands and the US Navy mounting freedom-of-navigation patrols
What does China claim?
China, the Philippines, Vietnam, Malaysia, Brunei and Taiwan all claim part of the South China Sea, using various historical and geographic arguments as justifications.
Vietnam claims sovereignty over the Paracel and Spratly islands, while the Philippines asserts ownership of the Spratly archipelago and the Scarborough Shoal. The Paracels are known in China as the Xisha and Vietnam as the Hoang Sa, and the Spratlys the Nansha.
Brunei and Malaysia claim sovereignty over southern parts of the sea and some of the Spratly Islands.
The Southeast Asian claimants say the Chinese boundary encroaches on their territorial waters as set out by international law, while Taiwan – viewed by Beijing as a renegade province – has a similar claim as the Chinese mainland.
Under the United Nations Convention on the Law of the Sea (Unclos), each country has the right to exploit natural resources within its exclusive economic zone, which extends 200 nautical miles (370km) from shore.
The South China Sea dispute explained
Why is the sea worth contesting?
The South China Sea is a key commercial thoroughfare connecting Asia with Europe and Africa, and is believed to have major reserves of natural gas and oil.
One-third of global shipping, or about US$3.37 trillion in international trade, passes through the South China Sea each year, including about 80 per cent of the oil imported by China, the world’s second-largest consumer of the resource.
The US Energy Information Administration estimates the area contains at least 11 billion barrels of oil and 190 trillion cubic feet of natural gas. Other estimates are as high as 22 billion barrels of oil and 290 trillion cubic feet of gas.
The disputed water also accounts for 10 per cent of fish caught globally, making it a key source of food for hundreds of millions of people.
Washington’s hardened position on Beijing’s claims in South China Sea heightens US-China tensions
Tensions have been rising in recent months, with other claimants and the US accusing China of worsening relations by increasing its infrastructure and military build-up in the area.
In mid-July, Washington said “Beijing’s claims to offshore resources across most of the South China Sea are completely unlawful” and threatened to sanction Chinese officials and companies that pursued “illegal” claims in the contested waters.
The US has stepped up its military presence, sending in warships and aircraft to keep tabs on China’s activities.
Although the US does not officially align with any of the claimants, it has wide-ranging security commitments in East Asia, and is allied with several countries bordering the sea, including the Philippines, Singapore and Vietnam.
The sea is also a vital trade route in the global supply chain, used by American companies that make goods in the region.
The US has conducted freedom-of-navigation operations, designed to challenge what it considers excessive claims and grant the free passage of commercial ships in its waters.
Is there progress on a resolution?
The Association of Southeast Asian Nations has been working with China on an official code of conduct to avoid clashes in the disputed waters. A binding agreement had been discussed for years to little avail but in November 2018 China said it hoped the consultation would be completed in three years.
The tribunal ruled in 2016 that Beijing had no historical rights to the waters within its nine-dash line. But China, which did not take part in the proceedings, refused to recognise the decision.
Southeast Asian nations have traditionally rejected looking for a bilateral solution with China, the region’s main economic and military power. Despite this, one year after the landmark ruling against China’s territorial claims, Philippine President Rodrigo Duterte agreed to resolve the dispute with China through bilateral talks.
In 2019, Vietnam said it could explore legal action to assert its maritime claim although it preferred to do so through negotiations.