CNOOC Pulls Back the Curtain

The South China Sea Frame-by-Frame, No. 2

The state-owned China National Offshore Oil Corporation (CNOOC) June 25 pulled back the curtain on Beijing’s ambitions in the South China Sea, announcing that it would open nine oil and gas blocks in the area to bidding by foreign companies. Such a move would not be surprising under normal circumstances. After all, Vietnam, the Philippines, Malaysia, and Brunei have all opened blocks in the South China Sea to bidding. Unfortunately, CNOOC’s blocks lie just off the Vietnamese coast and hundreds of miles from the Chinese mainland.

CNOOC Blocks

Hanoi predictably protested, calling the move an encroachment on its sovereignty and receiving at least tacit support from the other Southeast Asian claimants as well as the United States. Beijing meanwhile claimed that the tender, despite its provocative nature, was not coordinated by the government and only represented “normal business activity” by CNOOC. The implication being that CNOOC is free to open the blocks for bidding because they lie within China’s legal maritime claim.

From Hanoi’s point of view, this is patently ridiculous. The blocks in question lie almost entirely within the 200 nautical mile (nm) exclusive economic zone (EEZ) Vietnam is guaranteed under the UN Convention on the Law of the Sea (UNCLOS), shown below in blue. Meanwhile, the closest feature widely accepted as Chinese territory – Hainan Island – lies about 230 nm from even the closest block and nearly 600 nm from the farthest. This has led most observers to assume that China is claiming the blocks in question because they lie within the infamous “9 dash lines” that encompass nearly the entire South China Sea.


If true, that would fly in the face of not only international maritime law, but also official statements from Beijing. Chinese government officials, especially from the Foreign Ministry, have been attempting since February to bring the country’s gargantuan maritime claim into line with UNCLOS. To accomplish this, they have avoided referencing the “9 dash lines” and instead have insisted that Beijing’s claims extend only to the “islands and adjacent waters” of the sea as permitted under UNCLOS. Neither CNOOC nor the Chinese government has explicitly defended the nine blocks in question by referencing the “9 dash lines.” In fact, the “islands and adjacent waters” claim was reiterated as recently as August 4 in a statement by the Foreign Ministry.

Setting aside all other concerns, the most fundamental question in the case of CNOOC’s nine blocks is whether they can be justified with reference to “islands and adjacent waters.” Any such argument first rests on the (obviously) debatable claim that all the islands in the South China Sea are rightfully China’s. Second, it rests on the even more debatable claim that all the “islands” in question are in fact habitable and therefore entitled to their own EEZs under UNCLOS. The previous “Frame-by-Frame” blog elaborated more on the leap of faith required for these two assumptions. But, as in that case, giving China’s position the most generous possible interpretation also provides the most strenuous test of its claims.

The closest features to CNOOC’s blocks meeting the minimum requirements of an “island” under UNCLOS, meaning those above water at high tide, are the Paracel archipelago to the north and eight of the Spratlys to the east: Thitu, Spratly , Loaita, and Itu Aba Islands, Southwest and Northeast Cays, and Gaven, Fiery Cross, and Central Reefs. The Paracels are in this case being considered a single archipelago with connected archipelagic baselines as defined by UNCLOS. China declared archipelagic baselines for the Paracels in 1996 and, while the islands almost certainly do not qualify for such treatment, Beijing’s position will be accepted here for the sake of rigorously testing its claims


The 200 nm EEZs of these islands overlap with the EEZ of the Vietnamese mainland. That means that the most generous possible interpretation of China’s “adjacent waters” would be an equidistant line between the two. As with the previous “Frame-by-Frame,” this interpretation requires a radical break with international legal precedent, as the principle of equity enshrined in UNCLOS would make it impossible for such tiny features (the largest, Thitu Island, is less than half a mile across at its widest point) to encroach on the EEZ of hundreds of miles of Vietnamese coastline. But even interpreting this and all the other factors listed above in China’s favor fails to bring CNOOC’s actions into line with international law. As shown above, just over half of the blocks, or about 38,000 of nearly 62,000 square miles, fall within China’s possible legal claim. Through its support of CNOOC’s decision, Beijing has shown that the “9 dash lines” is still the operating principle behind its South China Sea claims, and the “islands and adjacent waters” rhetoric just empty rationalization for it.

This commentary is the second in cogitASIA's new blog series, The South China Sea Frame-by-Frame. It incorporates data and imagery from the CSIS Southeast Asia Program's innovative policy tool, The South China Sea in High Resolution. It original appeared on CSIS' Asia Policy blog, cogitASIA.

Gregory B. Poling
Senior Fellow and Director, Southeast Asia Program and Asia Maritime Transparency Initiative