WASHINGTON (Reuters) -Vietnam has significantly expanded island-building work in areas it claims in the Spratly Islands chain of the disputed South China Sea and will match and likely surpass the scale of such activity there by China, a U.S. think tank reported on Friday.
Recent satellite imagery showed that since the start of this year, Vietnam has expanded island-building to eight features previously untouched by a round of reclamation that began in 2021, the report from Washington’s Center for Strategic and International Studies said.
The report from CSIS’s Asia Maritime Transparency Initiative, said the imagery showed Vietnam has undertaken dredging and landfill work at Alison Reef, Collins Reef, East Reef, Landsdowne Reef and Petley Reefs.
The work meant that all 21 Vietnamese-occupied rocks and low-tide elevations in the Spratly Islands chain have now been expanded to include artificial land, when four years ago a majority hosted only isolated pillbox structures.
The report said new expansion had also begun at three features that already hosted medium-sized artificial islands created in earlier rounds of dredging: Amboyna Cay, Grierson Reef, and West Reef.
“As of March 2025, Vietnam had created about 70% as much artificial land in the Spratlys as China had,” it said. “Reclamation at these eight new features all but ensures that Vietnam will match – and likely surpass – the scale of Beijing’s island-building.”
China claims almost the entire South China Sea, despite overlapping claims by Brunei, Malaysia, the Philippines and Vietnam. Beijing has conducted extensive island-building work there opposed by the United States and its allies and partners.
The CSIS report said the images showed infrastructure, including munitions storage containers, was beginning to appear on Vietnamese claimed reefs where dredging work was approaching completion, such as Barque Canada Reef, Discovery Great Reef, Ladd Reef, Namyit Island, Pearson Reef, Sand Cay, and Tennent Reef.
It said the location of new structures and munitions depots seemed to preclude the possibility of full-length runways on some of the longer features and said a runway at Barque Canada was likely the only one being constructed to join Vietnam’s sole existing airstrip at Spratly Island.China and Vietnam’s Washington embassies did not immediately respond to requests for comment on the CSIS report.
In February, China said it opposes Vietnam’s construction activities on Barque Canada Reef, saying it was Chinese territory.
In 2016, the Permanent Court of Arbitration in the Hague ruled that China’s South China Sea claims were not supported by international law, a decision Beijing rejects.
(Reporting by David Brunnstrom; Editing by Daniel Wallis)
