Photo Credit: rri.co.id/Pradipta Rahadi

The initial spark of the territorial dispute between Indonesia's Aceh and North Sumatra provinces, centered around four crucial coastal islands—Lipan, Panjang, Mangkir Gadang, and Mangkir Ketek—dates back to 2007, according to the Home Ministry. What began as competing claims over their maritime boundaries escalated into a persistent problem due to the inability of the two provinces to reach an agreement. This lack of consensus led the matter to be referred to the central government, which subsequently issued a series of decrees in 2017, 2021, and 2022, consistently placing the islands under North Sumatra's jurisdiction. However, each of these directives was met with strong and consistent challenges from the Aceh administration, preventing any lasting resolution and allowing the century-old administrative uncertainty to fester.

The contention intensified in April 2025, when the Home Ministry issued its latest regulation administratively assigning these islands to North Sumatra. This decree ignited strong opposition from the Aceh government and its populace. Wali Nanggroe Aceh Malik Mahmud Al Haythar had even warned on June 17, 2025, that failure to return the islands could lead to tribal war and extreme tension. Coordinating Minister for Political and Security Affairs Budi Gunawan noted that President Prabowo prioritized national stability and justice, respecting historical records, cultural aspects, and the social dynamics of the Acehnese people in resolving this crucial matter.

The resolution was formally announced on Tuesday, June 18, 2025, by State Secretary Prasetyo Hadi, following a limited cabinet meeting led by President Prabowo via video conference from Russia. In attendance were Aceh Governor Muzakir Manaf, North Sumatra Governor Bobby Nasution, Home Minister Tito Karnavian, and House of Representatives Deputy Speaker Sufmi Dasco Ahmad. President Prabowo witnessed the signing of the resolution by both governors, officially concluding the contentious ownership dispute. This decisive action underscored the importance of national unity and stability for economic momentum, with Prabowo emphasizing that Indonesia is one nation and the Unitary State of the Republic of Indonesia (NKRI) must always be the foundation. Wali Nanggroe expressed his profound gratitude, noting that the news of the islands' return immediately eased tensions among the local community.

Prior to this definitive resolution, the dispute simmered through various Home Ministry decrees, including in 2007, 2017, 2020, 2021, and 2022, which initially placed the islands under North Sumatra's jurisdiction based on geographic position and multi-institutional spatial analysis. However, Aceh consistently rejected these rulings. The stakes were considerably heightened by the islands' proximity to significant energy reserves; they lie near the Offshore West Aceh (OSWA) oil and gas block, operated by Conrad Asia Energy Ltd. OSWA has estimated gas reserves of 296 billion cubic feet (BCF), and the adjacent Offshore North West Aceh (ONWA) is believed to contain up to 192 million barrels of oil and 1.1 trillion cubic feet (TCF) of gas. This proximity fueled concerns of political motivation behind the reclassification, despite unconfirmed direct reserves beneath the islands themselves.

Aceh's counter-arguments and historical evidence ultimately proved decisive in the resolution. Their claims were backed by colonial-era maps dating back to 1928, and a 1992 agreement between the governors. Former Vice President Jusuf Kalla, on June 15, 2025, emphatically declared the islands belong to Aceh historically and legally, citing Law No. 24 of 1956 and the 2005 Helsinki peace agreement, asserting a ministerial decree cannot override national legislation. Aceh also cited a 2009 administrative error in coordinate verification, 1965 land ownership certificates, and evidence of Aceh-built cultural and religious markers, such as graves and monuments, discovered during a 2022 factual survey that also noted Pulau Lipan was partially submerged. The 2008 national mapping initiative had controversially omitted these islands from Aceh's verified list.

The final decision, affirming Aceh's jurisdiction, was decisively influenced by the rediscovery of the original 1992 ministerial decree and its accompanying map, found in the Ministry of Home Affairs Archives Building on June 17, 2025. This document explicitly confirmed the four islands within Aceh's territory, corroborating its long-held claims. Home Minister Tito Karnavian, who had earlier expressed openness to legal challenges, emphasized his sole objective was to resolve the dispute, which he acknowledged was complex due to the need for UN registration for island naming. North Sumatra Governor Bobby Nasution had even proposed joint resource management prior to the ruling. This definitive resolution is widely hailed as a necessary conclusion and a wake-up call for the government regarding clearer regional border definitions, as noted by Herman Surparman of Jakarta-based think tank Regional Autonomy Watch (KPPOD). It serves to reinforce national unity and mitigate future inter-provincial conflicts, demonstrating a commitment to stable governance through dialogue and objective means, as pledged by the Coordinating Minister.

Sources: 

• "Prabowo to settle dispute over islands between Aceh-North Sumatra." The Jakarta Post, June 16, 2025. http://www.thejakartapost.com/indonesia/2025/06/16/prabowo-to-settle-dispute-over-islands-between-aceh-north-sumatra.html 
• "Prabowo to decide island dispute between Aceh-North Sumatra." Antara News, June 16, 2025. https://en.antaranews.com/news/359477/prabowo-to-decide-island-dispute-between-aceh-north-sumatra 
• "Tension grows between North Sumatra, Aceh over disputed border." The Jakarta Post, June 13, 2025. https://www.thejakartapost.com/indonesia/2025/06/13/tension-grows-between-north-sumatra-aceh-over-disputed-border.html 
• "Aceh protests transfer of disputed islands to North Sumatra." Indonesia Business Post, June 12, 2025. https://indonesiabusinesspost.com/4508/policy-and-governance/aceh-protests-transfer-of-disputed-islands-to-north-sumatra 
• "Dispute over 4 Islands between Aceh and North Sumatra Province Worsens, Prabowo Expected to Intervene." VOI.ID, June 13, 2025. https://voi.id/en/news/488718 
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• "Aceh Governor Rejects Home Minister's Decision on Disputed Islands." VOI.ID, June 12, 2025. https://voi.id/en/news/488982 "Prabowo gives nod to Aceh regaining control of disputed islands." The Jakarta Post, June 18, 2025. https://www.thejakartapost.com/indonesia/2025/06/18/prabowo-gives-nod-to-aceh-regaining-control-of-disputed-islands.html 
• "Prabowo Takes Over Aceh-North Sumatra Island Dispute, Decision to Be Made Next Week." Tempo Online, June 15, 2025. https://en.tempo.co/read/2017784/prabowo-takes-over-aceh-north-sumatra-island-dispute-decision-to-be-made-next-week 
• "Former VP Jusuf Kalla: Four Disputed Islands Belong to Aceh, Legally and Historically." Tempo Online, June 15, 2025. https://en.tempo.co/read/2017881/former-vp-jusuf-kalla-four-disputed-islands-belong-to-aceh-legally-and-historically 
• "Wali Nanggroe: 'There Will Be Tribal War Between Aceh, North Sumatra if 4 Islands Are Not Returned'." Tempo Online, June 18, 2025. https://en.tempo.co/read/2018795/wali-nanggroe-there-will-be-tribal-war-between-aceh-north-sumatra-if-4-islands-are-not-returned 
• "Aceh Reclaims Disputed Islands Near Offshore Oil Blocks After Prabowo’s Decision." Jakarta Globe, June 17, 2025. https://jakartaglobe.id/news/aceh-reclaims-disputed-islands-near-offshore-oil-blocks-after-prabowos-decision 
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