The recent expansion by Vietnam was the most noticeable at Barque Canada Reef, called Bai Thuyen Chai in Vietnam, where the report, produced by CSIS’ Asia Maritime Transparency Initiative (AMTI), said 85ha of land was created in the past year.
The report said Vietnam had started using cutter suction dredgers to “accelerate its dredging efforts”, and last month, it began dredging at two additional features, including South Reef and Central Reef.
It said Vietnam’s efforts have remained focused on dredging and landfill, with construction of infrastructure yet to begin.
China created more than 1,295ha of land from 2013 to 2016 in the area, the think-tank said.
In August, the Philippines, Malaysia, Taiwan and Vietnam rejected a map released by China that denotes its claims to sovereignty including in the South China Sea.