April 29, 2025
YOGYAKARTA – We have just witnessed a progressive development regarding borders in the South China Sea. The Commission I of the House of Representatives regrouped for a session to deliberate steps toward the ratification of the Indonesia-Vietnam Maritime Boundary Agreement. The April 23 hearing invited prominent academics to provide their views on the ratification of the agreement, which was signed on Dec. 22, 2022.
It is worth noting that border issues in the South China Sea have been a source of tension for a substantial period. Hence, the success of both nations’ agreement upon a maritime boundary is certainly historic. After 12 years of intensive negotiations, the ASEAN neighbors finally concluded an agreement on their maritime boundaries in the South China Sea.
The agreement of the exclusive economic zone (EEZ) deals only with water columns and not the seabed (continental shelf). For Indonesia, this was the first maritime boundary agreement established by the Jokowi administration and the first after Indonesia’s vision of becoming a global maritime fulcrum was coined. Indeed, this is a special agreement.
Between Vietnam and Indonesia, the 2022 agreement is the second after the first was signed in 2003 and ratified in 2007. It took the two countries almost two decades to come up with another agreement after long, intensive negotiations.
The 2003 agreement delimits the seabed between Indonesia and Vietnam, and it took almost 30 years to conclude. The agreement supplemented maritime boundary lines established by Indonesia and Malaysia around the same area in 1969.
Technically, the 2003 agreement connected Indonesia-Malaysia boundary lines, so altogether they enclosed an area of seabed that fell within Indonesia’s jurisdiction. This way, the division of the seabed among Indonesia, Malaysia and Vietnam in the South China Sea was made crystal clear.
There was no dispute on seabed ownership among the three neighbors. The only issue that remained pending was the division of water columns or exclusive economic zones (EEZ) for which Indonesia and Vietnam started intensive negotiations in 2010. On Dec. 22, 2022, the pending issue was successfully settled. Kudos to Indonesia and Vietnam for settling the dispute through negotiations.
What does the new agreement mean? First, Indonesia and Vietnam are in a good relationship, indicated by the fact that they managed to settle their differences through negotiation. Second, the division of rights and responsibilities between Indonesia and Vietnam in the South China Sea, both for the water column and the seabed, has now been made clear. This also means a new and clear era of resource management between the two countries.
Third, the agreement put some doubts regarding the possibility of settling boundaries in the South China Sea to rest. The agreement does not certainly settle every single conflict in the South China Sea, but it undoubtedly has brought new hopes of the possibility for dispute settlement.
For China in particular, the agreement can be seen as a clear statement regarding Indonesia’s and Vietnam’s views on the status of China’s nine-dash line. The 2022 agreement basically strengthens the 2003 agreement, confirming their refusal to the nine-dash line claim.
For Indonesia, the agreement has also answered some lingering questions regarding the settlement of the continental shelf and EEZ boundaries in the same maritime area. We have yet to see the 2022 agreement, but people will genuinely want to know whether the 2022 line coincides with the one established in 2003.
I personally think that the two different lines are in two different locations, which means that the two lines (EEZ and Continental Shelf boundaries) do not coincide. The new agreement will somehow serve as a reference for similar future cases, so it is important to clarify how the agreement treats the EEZ boundary concerning the existing continental shelf boundary of 2003.
What is next after the agreement? First, Indonesian and Vietnamese representatives need to return to their respective governments for the adoption and ratification of the agreement. This is what Indonesia is now doing. This might take time, but the step cannot be avoided for the agreement to be binding in their respective national laws. In my personal view, the ratification of the agreement is urgent.
Second, both countries need to agree on a law enforcement mechanism around the newly settled border. In general, each country will have its own mechanisms for enforcing the law in their respective EEZ, but it is always good to have mutual understanding on how lawbreakers will be treated.
Third, both countries need to take care of the technical aspects of the agreement. The use of charts, geodetic datum, coordinate systems and map projections are some of the matters that need to be taken into consideration for effective implementation of the agreement.
Fourth, education on the new borders for the public in general and especially for border regions is essential. Governments of both countries, in collaboration with educational institutions, need to educate their societies so that the issue can be more easily understood. The sudden change from an unclear border to the existence of a border warrants a change in public behavior. This undoubtedly requires adequate education.
Indonesia and Vietnam are two good friends and neighbors. Both are also the “giants” of Southeast Asia’s regional economy. The agreement on maritime boundaries they managed to reach confirms their close relationship and strong joint leadership in the region when it comes to settling boundary disputes.
We hope that the agreement will be ratified soon, and with that exemplary action, other countries will follow suit.
The writer is a lecturer and researcher on geospatial aspects of maritime law at the Department of Geodetic Engineering, Gadjah Mada University, Yogyakarta. The views expressed are his own.