TOKYO -- A 60-year-old dispute over the sovereignty of Sabah, Malaysia's second largest state, has recently reignited, creating tensions between Kuala Lumpur and Manila and adding a further complication to the many sovereignty issues in the South China Sea.
It began as a diplomatic spat on Twitter. "Sabah is not in Malaysia," Philippine Foreign Secretary Teodoro Locsin, Jr. tweeted in July, replying to a message by the U.S. Embassy in Manila about donations to Filipinos repatriated from Sabah.
Malaysian Foreign Minister Hishammuddin Hussein summoned the Philippine ambassador for a demarche shortly after Locsin's tweets. At the end of August, Malaysia made a formal complaint to the United Nations, known as a note verbale, about the Philippines.
Here are five things to know about the brewing dispute:
What is the Philippines' claim?
The Philippines derives its claim to Sabah from the Sultanate of Sulu, which once ruled the southernmost region of the Philippines. The sultanate asserts that the territory of North Borneo was a gift from the Sultan of Brunei, as a reward for Sulu's aid in a war in the 1600s.
Manila maintains that the sultanate's agreement with the British North Borneo Co. in 1878 was merely a lease, not a transfer of sovereignty. Muedzul Lail Tan Kiram, the reigning sultan, told the Nikkei Asian Review that his grandfather agreed to integrate Sulu into an independent Philippines to further his effort to reclaim Sabah.
But until now, only two Philippine presidents, Diosdado Macapagal and the dictator Ferdinand Marcos, have actively espoused Sulu's claim. Since Marcos, who was ousted in 1986, the Philippine government has not formally recognized the Sultan of Sulu.
What is Malaysia's view?
Kuala Lumpur insists the British North Borneo Co.'s payments were installments to purchase the territory from Sulu. In that case, sovereignty was transferred to Malaysia when it succeeded British Malaya.
In another signal that Kuala Lumpur would not give up the oil and gas-rich Sabah, nine Filipinos are awaiting the death penalty in Malaysian custody, including Hushin Kiram, a cousin of Sultan Muedzul. Kiram was arrested in 2013 after leading a failed takeover of Sabah, at the command of his father Jamalul Kiram III, a pretender to the Sulu throne.
Locsin's Sabah tweets came hours after President Rodrigo Duterte declared in a national address that the Philippine claim to the South China Sea was "inutile" because China was already "in possession" of the disputed waters. The unscripted statement was roundly criticized, as territorial claims are typically a nationalist rallying cry.
Locsin is seeking to revive the Office of North Borneo Affairs, a division of the Department of Foreign Affairs that was shuttered after the Marcos administration. Congress is considering a bill to include the South China Sea territories, known as the West Philippine Sea, and Sabah in Philippine passports, which contain a map of the country.
Former Sabah chief minister Yong Teck Lee called it a "provocative" move. Interestingly, in 2012, Manila ordered customs officials not to stamp Chinese passports printed with the controversial Nine-Dash Line, which encompasses China's territorial claims.
Perhaps more urgently, tens of thousands of Filipinos are living without proper documentation in Sabah. Hundreds were deported to the Philippines as COVID-19 spread in the state. Because it considers Sabah its territory, the Philippines has historically refused to open a local consulate.
How does it affect the South China Sea?
The question of who owns Sabah affects territorial projections in the South China Sea -- not only for Malaysia and the Philippines, but also for Brunei and Indonesia. Such disputes between members of the Association of Southeast Asian Nations have stood in the way of a united stance against a bigger urgent threat -- China's militarization of the disputed waters.
Member states set aside their territorial claims in the 1960s to pave the way for the formation of ASEAN. Sabah's Chief Minister Shafie Apdal has now asked the Malaysian government to bring the Philippines' assertion to ASEAN, which has 10 country-members. But it is unclear whether the organization, which acts by consensus, will be an effective arbiter.
What happened in the recent election in Sabah?
A coalition formed by parties in Malaysian Prime Minister Muhyiddin Yassin's government won a state election in Sabah on Saturday, easing pressure on the embattled leader who faces a challenge from opposition leader Anwar Ibrahim.
The Muhyiddin-led coalition, Sabah People's Movement, received a mandate from some 1.1 million voters on the Borneo island and crossed the 37 assembly-seat threshold to form the next state government.
The coalition defeated sitting Chief Minister Shafie and his Sabah Heritage Party, which won at least 21 seats. The victory boosted Muhyiddin's standing at the federal level, where he faced a leadership challenge from Anwar, who claimed to have the support of the majority of members of parliament.