August 12, 2025
JAKARTA – Indonesia has called for diplomacy to resolve the long-standing dispute over Ambalat after Malaysia recently reasserted its claim to the resource-rich maritime area as part of its territory.
“[It will be] resolved amicably, peacefully [through] diplomacy,” Foreign Minister Sugiono told reporters on Friday, as quoted by Tempo.
While acknowledging the complexity and longevity of the dispute, Abdul Kadir Jaelani, the ministry’s director general for Asia-Pacific and African affairs, echoed the stance by saying, “Indonesia adheres to ASEAN principles of resolving differences through peaceful means,” as quoted by Antara.
On Thursday, President Prabowo Subianto said the government was seeking a peaceful resolution, noting that both sides had shown goodwill.
The statements follow Malaysian Foreign Minister Mohamad Hasan asserting on Tuesday that Ambalat, which the country refers to as blocks ND6 and ND7, is part of Malaysia.
“These blocks fall within our sovereign area, therefore the accurate reference in line with Malaysia’s stance is Laut Sulawesi [Sulawesi Sea],” he told the lower house of parliament on Tuesday, as quoted by The Star, asking lawmakers to refrain from using the region’s Indonesian name, Ambalat.
The disputed area spans 15,235 square kilometers near the maritime border between North Kalimantan and Malaysian state of Sabah. Located off the northeastern coast of the island of Borneo, which the two countries share along with Brunei to the north, this particular boundary between Indonesia and Malaysia’s continental shelf has remained unresolved for decades, with negotiations still ongoing.
A colonial-era agreement in 1891 placed Ambalat in Indonesian territory, which was reaffirmed in the 1969 Indonesia-Malaysia Continental Shelf Boundary Treaty. However, Malaysia claimed the maritime area as its territory in a map issued in 1979, which later triggered a dispute over the nearby islands of Sipadan and Ligitan.
The International Court of Justice eventually awarded the two islands to Malaysia in 2002.
Foreign minister Mohamad referred to this ruling on Tuesday, saying it strengthened Malaysia’s claim to Ambalat, while adding that Kuala Lumpur would handle the matter peacefully.
“We enjoy good relations with Indonesia, 98 percent of it is positive. Let us negotiate the remaining 2 percent calmly, as we don’t want to go to war over it,” he said.
Earlier in June, when Malaysian Prime Minister Anwar Ibrahim was in Jakarta to attend the two countries’ annual consultation, President Prabowo announced an agreement to jointly explore and exploit natural resources in Ambalat.
“We agreed that while resolving the legal matters, we will begin an economic cooperation under what we call ‘joint development’. Whatever we find in the sea, we will exploit together,” Prabowo said at the time.
Following the meeting, Anwar said it would not be wise to delay economic cooperation in Ambalat simply because the related maritime boundaries had yet to be formally resolved.
However, the plan remains in its exploratory phase to date.
Not likely to escalate
Aristyo Darmawan, an international law expert at the University of Indonesia (UI), said on Saturday that opposing claims over maritime boundaries and their names were common between neighboring countries.
Aristyo said the dispute over Ambalat was unlikely to escalate, especially since Jakarta and Kuala Lumpur planned to codevelop the area, which he described as a “pragmatic” move to create stability and generate mutual economic benefits while territorial negotiations continued.
“The United Nations Convention on the Law of the Sea [UNCLOS] stipulates that even when maritime boundary negotiations are ongoing, countries can enter joint development agreements without affecting the negotiation process,” he added.
He also suggested that Indonesia continue the talks while freely using Ambalat as its preferred name.
UI international law professor Hikmahanto Juwana described the joint development agreement as a reasonable interim solution for the disputed area.
“Neither side will withdraw its claim over the continental shelf boundary, and the boundary dispute could continue indefinitely,” he said.
“But if both sides agree to a joint development rather than leaving the natural resources untapped while awaiting a resolution, there will no longer be an issue over the maritime border.”