China building largest artificial island in South China Sea – report

MANILA, Philippines — China is constructing what could become its largest artificial island in the South China Sea, according to a new report, signaling renewed large-scale reclamation activity in disputed waters.

The project at Antelope Reef in the Paracel Islands could rival or even surpass the size of China’s biggest outposts in the region, the Asia Maritime Transparency Initiative (AMTI) of the Washington-based think tank Center for Strategic and International Studies (CSIS) said in its report.

Satellite imagery shows Beijing has reclaimed about 1,490 acres of land at Antelope Reef, placing it close in size to Mischief (Panganiban) Reef, currently China’s largest outpost at about 1,504 acres.

"Antelope Reef is set to become China’s largest feature in the Paracels and potentially in the entire South China Sea," the report said.

The dredging began in October 2025, marking China’s first major island-building activity in the South China Sea since 2017.

AMTI said the size of the new landmass could allow construction of a 9,000-foot runway, similar to those built on other Chinese-occupied features.

Implications

The reef’s lagoon and expanded land area could support naval, coast guard and maritime militia operations, as well as military infrastructure such as surveillance systems and missile facilities, the think tank said.

The project, it explained, would likely extend China’s reach closer to Vietnam’s coastline and provide additional capacity for its air and naval assets in the northern South China Sea.

While the expansion may not drastically alter the overall balance of power, it signals Beijing’s continued ability to expand its presence in contested areas.

It may also be a signal to Vietnam, analysts said.

"Beijing is certainly signaling its ability to continually expand its occupied features—a message perhaps intended most directly for Hanoi, whose own reclamation and landfill activities in the Spratlys remain ongoing," the report noted.

Dispute with Vietnam. The Paracel Islands, where Antelope Reef is located, are claimed by both China and Vietnam, though they have been under Chinese control since the 1970s.

The islands lie in the northern part of the South China Sea, a region that is a key shipping route and a long-standing flashpoint involving overlapping territorial claims.

Broader pattern. China has previously built large artificial islands in the Spratly Islands claimed by the Philippines as Kalayaan Islands, including at Mischief (Panganiban) Reef, Subi (Zamora) Reef and Fiery Cross (Kagitingan) Reef, where the Asian power constructed airstrips, ports and military facilities.

The report noted that while the final use of the new facilities remains uncertain, "the projected scale alone suggests that Antelope could become one of the most important outposts China has built in the South China Sea." — Camille Diola