Ratifying the Indonesia-Vietnam EEZ maritime delimitation agreement serves national and regional best interests
Ratifying the Indonesia-Vietnam EEZ Maritime Delimitation Agreement Serves National and Regional Best Interests
WRITTEN BY ARISTYO RIZKA DARMAWAN AND JOHN BRADFORD
14 August 2025
It has been more than a year since Indonesia and Vietnam concluded an Exclusive Economic Zone (EEZ) maritime delimitation Agreement, yet the cartographic details of that deal remain unavailable to the public, and there has seemingly been little progress towards ratification of the agreement by the Indonesian parliament. When the agreement was signed in late 2023, scholars generally heralded it as a positive development, not only for Indonesia and Vietnam's relationship but also for broader issues related to regional peace and security. It is unusual for an Indonesian treaty ratification process to extend beyond a single parliamentary session, and a failure to ratify the agreement would be most unfortunate.
The agreement came after more than 12 years of maritime delimitation negotiations between Indonesia and Vietnam. During these long negotiations, there were instances when fishers from both countries operated in the undelimited maritime area, which often led to tension and escalation between law enforcement institutions. Physical clashes involving national forces were documented, including on video. The new agreement should prevent such escalations from reoccurring, as both sides will be able to respect a clear maritime boundary.
Despite promise, progress is stalled
While the details of the agreement have not been made available to the public and it has yet to be formally brought into force, it is already having a positive effect by reducing the risks associated with Indonesia-Vietnam clashes. The two nations’ coast guards and navies appear to be respecting the agreement, based on the patrol routes of their vessels and statements from their representatives. Furthermore, maritime domain awareness analysis conducted by the Indonesian Ocean Justice Initiative shows that Vietnamese fishing vessels which previously ventured well into the Indonesian-claimed North Natuna Sea area now rarely cross the line marking the northern edge of Indonesia’s continental shelf. This suggests that while the cartographic details of the agreement are not yet known to the public, Vietnamese fishers are under orders to respect them.
Ratifying the agreement will cement the hard-earned and very positive arrangement. Without ratification, however, Vietnam may perceive Indonesia as not fully upholding its commitments, increasing the risk of mutual backsliding. How the Vietnamese respond to such a scenario remains to be seen.
Ratification of the EEZ agreement provides a good opportunity for Indonesia to clarify its position by denying the validity of China’s Nine-Dash Line claim while simultaneously preserving its interests and advancing good relations with an important neighbour.
Ratifying the deal with Vietnam would also demonstrate Indonesia’s readiness to take firm stances in defence of its sovereign interests while simultaneously finding room to compromise in support of the greater good. This dual approach would enhance Indonesia’s diplomatic credibility and strengthen its leadership concerning important maritime affairs such as the ongoing negotiations over the South China Sea Code of Conduct. Furthermore, the agreement could set another positive precedent for ASEAN states in settling maritime disputes peacefully through negotiations.
During a meeting with Vietnamese Communist Party Secretary General To Lam in March 2025, President Prabowo Subianto reiterated Indonesia’s commitment to ratifying the EEZ delimitation agreement. In late April, the Indonesian parliamentary commission overseeing the agreement held hearings with experts, who positively appraised the agreement as an opportunity to resolve issues with Vietnam and strengthen the Indonesian position in South China Sea disputes. Then, in May 2025, commission member Nico Siahaan told the media that it was set to ratify the agreement within the week. However, despite these positive gestures, the agreement remains unratified. With Parliament now in recess until mid-August, further delays are expected.
There may be multiple factors behind the stall, but insiders point to a China factor, as the EEZ agreement involves sea space within China’s Nine-Dash Line claim. Chinese Ministry of Foreign Affairs spokesperson Hua Chunying has stated that China was in close communication with Indonesia and Vietnam because, in their view, the negotiations could undermine stability in the South China Sea and the states’ bilateral relations with China. It seems likely that such diplomatic communications from Beijing are an important factor in the Parliamentary ratification roadblock.
This China factor seems to have also attracted the attention of Washington. According to media reports, including the IDN Times, the ratification of the Indonesia-Vietnam EEZ agreement was raised by the United States during the tariff negotiations. Although unrelated to US-Indonesia trade, President Trump has a track record of using tariffs as levers to advance other American geopolitical interests. This likely reflects US concern that Indonesia is bowing to Chinese pressure on a matter of regional significance. Indeed, South China Sea issues featured heavily in the tariff negotiations. Non-ratification of the EEZ agreement to appease Chinese preferences would amount to de facto recognition of the Nine-Dash Line claim. This would be a departure from Indonesia’s past position that it is not a disputant in the South China Sea, and from international law, which has shown the Nine-Dash Line to be completely baseless.
Why ratification matters
Ratification of the EEZ agreement could provide an important clarification of Indonesia’s stance on the Nine-Dash Line and advance Indonesia’s credibility and leadership on South China Sea issues within ASEAN – areas where Indonesia's strength has slipped in the past year. The Indonesia-China Joint Statement issued during Prabowo’s 2024 visit to China acknowledged an “overlapping claim” between Indonesia and China, which many scholars have interpreted as being a form of recognition of China’s Nine-Dash Line claim. With this perception, Indonesia will be regarded as the first country in ASEAN to recognise China’s amorphous claim. It might also lead to Indonesia losing its credibility in ASEAN, particularly in its role leading the ongoing negotiation of the ASEAN-China Code of Conduct.
Although the Indonesian Ministry of Foreign Affairs has clarified that Indonesia does not recognise the Nine-Dash Line, scholars – including one of the co-authors and others – point out that it is difficult to understand this interpretation since China’s only claims to this area relate to the Nine-Dash Line. Ratifying the agreement would put this debate to rest by documenting Indonesia’s position in law.
President Prabowo has regularly reiterated his commitment to ensuring that Indonesia ratifies the agreement, and now the ball is with the parliament. With the president’s ruling coalition enjoying a majority in the parliament, it should have been easy to get legislative support for the president’s political will to pass the agreement. Failing to do so would raise additional questions about the underlying factors that stalled the ratification process.
Ratification of the EEZ agreement provides a good opportunity for Indonesia to clarify its position by denying the validity of China’s Nine-Dash Line claim while simultaneously preserving its interests and advancing good relations with an important neighbour. Doing so will help retain its regional leadership, particularly regarding South China Sea issues. Failure to do so could harm Indonesia’s reputation and undermine its credibility with Vietnam, fellow ASEAN members, and global partners.
DISCLAIMER: All views expressed are those of the writers and do not necessarily represent that of the 9DASHLINE.com platform.
Authors’ biographies
Aristyo Rizka Darmawan is a lecturer in international law at Universitas Indonesia and a PhD Scholar at the Australian National University.
John Bradford is the Executive Director of the Yokosuka Council on Asia-Pacific Studies and an Adjunct Senior Fellow in the RSIS Maritime Security Programme. Image credit: Flickr/U.S. Pacific Fleet.
*A shorter version of this commentary was published by the S. Rajaratnam School of International Studies on 4 July 2025. This version has been updated to reflect the latest developments.