.
The 
South China Sea is a 
marginal sea of the 
Western Pacific Ocean. It is bounded in the north by the shores of 
South China (hence the name), in the west by the 
Indochinese Peninsula, in the east by the islands of 
Taiwan and northwestern 
Philippines (mainly 
Luzon, 
Mindoro and 
Palawan), and in the south by 
Borneo, 
eastern Sumatra and the 
Bangka Belitung Islands, encompassing an area of around 
3,500,000 km2 (1,400,000 sq mi). It communicates with the 
East China Sea via the 
Taiwan Strait, the 
Philippine Sea via the 
Luzon Strait, the 
Sulu Sea via the 
straits around Palawan (e.g. the 
Mindoro and Balabac Strait), the 
Strait of Malacca via the 
Strait of Singapore, and the 
Java Sea via the 
Karimata and Bangka Strait. The 
Gulf of Tonkin is also part of the South China Sea, and the shallow waters south of the 
Riau Islands are also known as the 
Natuna Sea.
The South China Sea is a region of 
tremendous economic and geostrategic importance. 
One-third of the world's 
maritime shipping passes through it, carrying over US$3 trillion in trade each year. 
Huge oil and natural gas reserves are believed to lie beneath its seabed. It also contain 
lucrative fisheries, which are crucial for the 
food security of millions in 
Southeast Asia.
The 
South China Sea Islands, collectively comprising several 
archipelago clusters of mostly small uninhabited 
islands, islets (cays and shoals), reefs/atolls and 
seamounts numbering in the hundreds, are subject to 
competing claims of sovereignty by several countries. These claims are also reflected in the variety of names used for the islands and the sea.
The 
Strait of Malacca (
Malay: Selat Melaka, 
Indonesian: Selat Malaka, 
Thai: ช่องแคบมะละกา, 
Tamil: மலாக்கா நீரிணை, Malākkā nīriṇai, 
Chinese: 馬六甲海峽/马六甲海峡) or 
Straits of Malacca is a narrow stretch of water, 
580 mi (930 km) in length, between the 
Malay Peninsula (
Peninsular Malaysia) and the 
Indonesian island of Sumatra. As the 
main shipping channel between the 
Indian Ocean and the 
Pacific Ocean, it is one of the most important 
shipping lanes in the world. It is named after the 
Malacca Sultanate that ruled over the 
archipelago between 1400 and 1511, the center of administration of which was located in the modern-day state of 
Malacca, 
Malaysia.
From an economic and strategic perspective, the Strait of Malacca is one of the most important shipping lanes in the world.
The strait is the main shipping channel between the 
Indian Ocean and the 
Pacific Ocean, linking major Asian economies such as 
India, 
Thailand, 
Indonesia, 
Malaysia, 
Philippines, 
Singapore, 
China, 
Japan, 
Taiwan, and 
South Korea. The Strait of Malacca is part of the 
Maritime Silk Road that runs from the Chinese coast towards the southern tip of 
India to 
Mombasa, from there through the Red Sea via the 
Suez Canal to the Mediterranean, there to the Upper Adriatic region to the northern Italian hub of 
Trieste with its rail connections to 
Central Europe and the 
North Sea. Over 
94,000 vessels pass through the strait each year (
2008) making it the 
busiest strait in the world, carrying about 
25% of the world's traded goods, including 
oil, Chinese manufactured products, coal, palm oil and Indonesian coffee. About a 
quarter of all oil carried by sea passes through the Strait, mainly from 
Persian Gulf suppliers to Asian markets. In 
2007, an estimated 13.7 million 
barrels per day were transported through the strait, increasing to an estimated 15.2 million 
barrels per day in 
2011. In addition, it is also 
one of the world's most congested shipping choke points because it narrows to only 
2.8 km (1.5 nautical miles) wide at the 
Phillip Channel (close to the south of 
Singapore).
The 
maximum size (specifically 
draught) of a vessel that can pass through the Strait is referred to as 
Malaccamax, that is, for some of the world's largest ships (mostly 
oil tankers), the Strait's minimum depth (25 metres or 82 feet) is not deep enough. This is determined by the 
relatively shallow Singapore Strait, which provides passage to the 
Karimata Strait in the east. The next closest passageway (the 
Sunda Strait between 
Sumatra and Java) is 
even more shallow and narrow. Therefore, ships 
exceeding the Malaccamax must 
detour a few thousand nautical miles and use the 
Lombok Strait, Makassar Strait, Sibutu Passage, and Mindoro Strait instead.
Piracy has been a 
problem in the strait. Piracy had been high in the 2000s, with additional increase after the events of 
September 11, 2001. After attacks rose again in the first half of 2004, regional navies stepped up their patrols of the area in July 2004. Subsequently, attacks on ships in the Strait of Malacca dropped, to 79 in 2005 and 50 in 2006. Reports indicate that attacks have dropped to 
near-zero levels in recent years.
There are 
34 shipwrecks, some dating to the 1880s, in the local TSS channel (the channel for commercial ships under the global 
Traffic Separation Scheme). These pose a 
collision hazard in the 
narrow and shallow strait.
On 20 August 2017, the 
United States Navy destroyer USS John S. McCain lost ten of its crew's lives in a collision with the merchant ship 
Alnic MC a short distance east of the strait whilst full steering capabilities had been lost and making a series of errors in attempted mitigation, its external lights being changed to "red over red" ("vessel not under command").
Another risk is the 
annual haze due to 
bush fires in Sumatra, 
Indonesia. It may 
reduce visibility to 
200 metres (660 ft), forcing ships to slow down in the busy strait. The strait is frequently used by 
ships longer than 350 metres (1,150 ft).
 Thai Canal: 
Thailand has developed plans to divert much of the strait's traffic and hence some of its economic significance to a shorter route: the Thai government has several times proposed 
cutting a canal through the 
Isthmus of Kra, saving around 960 kilometres (600 mi) from the journey between the two oceans. 
China has offered to cover the costs, according to a report leaked to 
The Washington Times in 2004. Nevertheless, and despite the support of several Thai politicians, the 
prohibitive financial and ecological costs suggest that such a canal will 
not be built.
An alternative is to install a 
pipeline across the 
Isthmus of Kra to carry oil to ships waiting on the other side. Proponents calculate it would cut the cost of oil delivery to 
Asia by about 
$0.50/barrel ($3/m3). 
Myanmar has also made a similar pipeline proposal.
The 
South China Sea disputes involve both island and maritime claims by several 
sovereign states within the region, namely 
Brunei, the 
People's Republic of China (PRC), 
Taiwan (Republic of China/ROC), 
Indonesia, 
Malaysia, the 
Philippines, and 
Vietnam. An estimated 
US$3.37 trillion worth of 
global trade passes through the South China Sea annually, which accounts for a 
third of the global maritime trade. 
80 percent of China's energy imports and 
39.5 percent of China's total trade passes through the South China Sea.
The 
disputes involve the 
islands, reefs, banks, and other features of the South China Sea, including the 
Spratly Islands, Paracel Islands, Scarborough Shoal, and various boundaries in the 
Gulf of Tonkin. There are further disputes, such as the waters near the 
Indonesian Natuna Islands, which many do not regard as part of the South China Sea. Claimant states are interested in retaining or acquiring the rights to 
fishing stocks, the exploration and potential exploitation of 
crude oil and natural gas in the seabed of various parts of the South China Sea, and the 
strategic control of important shipping lanes.
Since 
2013, the 
PRC has resorted to 
island building in the Spratly Islands and the Paracel Islands region. According to Reuters, island building in the South China Sea primarily by Vietnam and the Philippines has been going on for decades; while China has come late to the island building game, its efforts have been on an unprecedented scale as it had from 
2014 to 2016 constructed more new island surface than all other nations have 
constructed throughout history and as of 2016 placed 
military equipment on one of its artificial islands unlike the other claimants. A 2019 article in 
Voice of America that compared China and Vietnam's island building campaign in the South China Sea similarly noted that the reason why 
Vietnam in contradistinction to China has been subject to little international criticism and even support was because of the 
slower speed and 
widely perceived defensive nature of its island-building project.
China's actions in the South China Sea have been described as part of its 
"salami slicing" strategy, and since 2015 the United States and other states such as 
France and the 
United Kingdom have conducted 
freedom of navigation operations (FONOP) in the region. In July 2016, an arbitration tribunal constituted under Annex VII of the 
United Nations Convention on the Law of the Sea (UNCLOS) ruled against the PRC's maritime claims in 
Philippines v. China. The tribunal did not rule on the ownership of the islands or delimit maritime boundaries. Both the 
People's Republic of China and the
 Republic of China (Taiwan) stated that they 
did not recognize the tribunal and insisted that the matter should be resolved through bilateral negotiations with other claimants. On 
September 17, 2020, 
France, Germany, and the 
United Kingdom issued a joint 
note verbale recognizing the PCA ruling and 
challenging China's claims.