Why is Vietnam rapidly building on South China Sea reefs?

Satellite pictures have shown that large-scale land reclamation is underway on coral island reefs controlled by Vietnam. The work, identified in 2022, has dramatically increased in scope this year and looks set to continue.

The activity is centred around six key reefs in the Spratly Islands in the South China Sea – one of the most geopolitically contested regions on Earth. Although the purpose of this work is not clear, it is contributing to an atmosphere of escalating regional tension. 

The Spratlys are not controlled by any single country but fall variously within the 200 nautical mile exclusive economic zones of Malaysia, Brunei, Vietnam and the Philippines, as well as China’s contested claim to a large area of the South China Sea, bounded by the ‘nine-dash-line’. Taiwan too claims sovereignty over islands in the region.

The Spratlys are strategically important because they provide claimant states access to the South China Sea’s international shipping lanes, rich fishing grounds and significant gas and oil deposits. China for example – which controls three of the largest reefs in the Spratlys – is currently engaged in a standoff with the Philippines for control of Second Thomas Shoal. 

Expanding regional presence

Small changes to Vietnam’s Spratly Island outposts were first observed a decade ago, but their pace and scale have increased dramatically since 2022.

At Barque Canada Reef, sediment-pouring operations have doubled its size and turned it into Vietnam’s largest outpost in the Spratlys. Much of the work is expanding the northern ring of the atoll, which the Asia Maritime Transparency Initiative – a Washington-based organization monitoring the South China Sea – suggests could now host a three-kilometre runway capable of landing long-range military aircraft.

Namyit Island has also seen big changes since 2022. It now has a new harbour dredged out of the atoll’s centre and has grown to become Vietnam’s second largest feature in the archipelago. It lies just north of the Chinese-controlled Union Banks shoal, where China’s maritime militia has been trying to prevent Philippine forces supplying a military detachment aboard the BRP Sierra Madre at Second Thomas Shoal. 

Mixed motives

The impetus behind Vietnam’s reclamation projects is contested. Officially the government in Hanoi has not commented on these developments, but routinely criticizes the activities of other claimant states which it sees as infringements of its sovereignty.

Vietnam’s longstanding history of confrontation with China, including a string of standoffs between maritime militia, coastguards and law enforcement agencies, could be playing into its decision-making in the Spratlys. The last major skirmish took place over a decade ago.

Nga Pham, a Vietnamese journalist, said: ‘The official narrative is always that Vietnam is doing some small-scale construction to strengthen weather shelters for fishermen and prevent erosion. But it is all being done by the military and it’s fair to say that Hanoi has been militarizing its maritime features but at a much slower pace and at a scale far smaller than that of China.’

Détente with Beijing?

Yet, with Beijing’s attention focused on forcing a withdrawal of the Philippines from Second Thomas Shoal, it is more likely that Vietnam is using the relative lull in Sino-Vietnamese tensions to reinforce its position in the South China Sea and hedge its bets for any future escalation. 

Bill Hayton, associate fellow in the Asia-Pacific Programme of Chatham House, said: ‘As far as we know, China has not tried to interfere with Vietnam’s construction on these reefs, which is a huge contrast with its ongoing efforts to block the Philippines’ attempts to reinforce the BRP Sierra Madre.’

It is also telling that despite China’s routine pushback on Vietnam’s claims to the Spratly Islands, it has offered little comment on Hanoi’s current land-reclamation operations. This silence, alongside the pro-Chinese leadership changes underway in Hanoi, could signal a reluctance from Beijing to escalate tensions in the South China Sea. 

‘The new leadership in Hanoi has far more in common ideologically with China and Russia than with the West,’ said Hayton. ‘So, it has even less desire to upset relations with Beijing than its predecessors and is unlikely to make waves in the South China Sea for the time being.’

With further land reclamation operations expected on at least four out of the six reefs, the final scope of Hanoi’s ambitions in the Spratlys remains unclear. Although tensions with China may be subsiding, the Maxar satellite imagery suggests that for Vietnam, and other countries in the region, these islands will remain at the centre of a slow-burning, geostrategic tussle.