HANOI (AFP) - Vietnam has started dredging work on a reef in the South China Sea, fresh satellite images appear to show, a move that could provoke Beijing which claims most of the disputed waterway.
An image of the small Ladd Reef in the Spratly Islands, where Vietnam has a lighthouse, shows several vessels in a carved out embankment on the reef's edge.
Sediment can be seen leaking out into the ocean, according to the November 30 image provided to AFP on Friday (Dec 9) by US-based Planet Labs, a satellite imaging company.
A July picture from Planet Labs shows no breach to the reef's embankment, suggesting the work began in recent months.
Vietnamese officials did not respond to a request for comment.
The images follow photos published last month from US-based Asia Maritime Transparency Initiative that showed Vietnam had extended a runway and was building hangars capable of hosting military equipment on a different island in the Spratlys also claimed by Beijing.
But Vietnam's latest moves remain small-scale compared to China's build-up in the waterway, where it has constructed several islands capable of supporting military facilities.
Though the intent of the work depicted in the photos cannot be confirmed, Vietnam expert Carl Thayer told AFP that Hanoi might be trying to "stock up" ahead of a code of conduct agreement between various claimants in the South China Sea expected next year.
"Vietnam is moving beyond the status quo," said Thayer, a professor at the University of New South Wales.
"My speculation was that if we are moving toward some diplomatic end game at some point in the next year or two, then Vietnam looks like it's trying to get as much as it can before it's prohibited," he added.
Thayer said China can "make a meal out of" Vietnam's latest apparent dredging work, but said it does not appear to be for military purposes or explicitly threaten Beijing.
The two countries have long traded barbs over disputed territory in the sea. In 2014 China moved a controversial oil rig into contested waters, prompting riots in Vietnam.
Tensions have eased slightly in recent months but the issue remains incendiary on both sides.
The sea is also claimed by the Philippines, Brunei, Malaysia and Taiwan and is rich in energy reserves, fishery resources and is a busy shipping route.