Sharp perspectives on the issues shaping Southeast Asia
By TENGKU NOOR SHAMSIAH TENGKU ABDULLAH
Column No. 4 — 6 April 2026 — TNS News
As the Iran war enters its sixth week with no ceasefire in sight, ASEAN finds itself in the eye of multiple storms simultaneously. President Donald Trump issued an ultimatum over the weekend demanding that Iran reopen the Strait of Hormuz by Tuesday or face attacks on its power plants. Malaysia’s Prime Minister has emerged as an unexpected but consequential back-channel diplomat, personally securing safe passage through Hormuz for Malaysian vessels. And a candid admission this week — that PETRONAS is now a net importer of fuel — has shattered a long-held assumption about Malaysia’s energy insulation.
For Southeast Asia, this may be the most intense week of an already turbulent year.
On Sunday, 5 April, Trump delivered what may be the war’s most direct ultimatum yet: reopen the Strait of Hormuz by Tuesday at 8pm Eastern Time or Iran would face attacks on its power plants. In an expletive-laden post on Truth Social, he warned Tehran it would be “living in Hell” if the waterway remained closed.
Oil markets reacted immediately. US crude surged above USD114 per barrel on Sunday evening.
The ultimatum signals the conflict may be entering a sharper phase, even as both sides intermittently signal a desire for a diplomatic exit neither has yet fully embraced.
For Southeast Asia, these developments are far from abstract geopolitical theatre. They translate directly into fuel supply risks, rising food prices, fiscal pressure, and economic survival.
Fatih Birol, head of the International Energy Agency, warned that April will be worse than March. In March, some pre-war cargoes were still reaching Asian ports. “In April,” Birol stated bluntly, “there is nothing.”
The agency estimates the conflict has already removed 12 million barrels per day from global supply — more than the combined losses during two oil shocks of the 1970s.
Malaysia’s Diplomatic Moment and Its Energy Wake-Up Call
The most consequential regional development this week has come from Malaysia.
Prime Minister Datuk Seri Anwar Ibrahim revealed on Saturday, 4 April, that PETRONAS is now a net importer of fuel — no longer the exporter it was widely assumed to be.
Speaking in Ipoh during the Perak Madani Rakyat Programme, Anwar was direct.
“Petronas is now a net importer; we need to buy oil. Supply for April and May is sufficient, but for June it is still uncertain.”
The admission reframes Malaysia’s position in the crisis.
The country exports its lighter premium-grade crude while importing heavier Middle Eastern crude for domestic refining — more than half of which originates from the Gulf. With the Strait of Hormuz effectively closed, that supply chain has been disrupted.
The government is currently spending RM4 billion per month to maintain the subsidised RON95 price of RM1.99 per litre.
“This is no small feat,” Anwar acknowledged.
Deputy Prime Minister Fadillah Yusof announced a five-point national response plan on 2 April focusing on:
• supply security
• stakeholder engagement
• price stabilisation
• energy conservation
• public communications
Measures include directing public sector workers and government-linked companies to adopt work-from-home arrangements beginning 15 April.
Yet Malaysia’s most striking role this week has been diplomatic.
Anwar disclosed that several Arab leaders have contacted him directly to convey messages to Iranian President Masoud Pezeshkian recognising Malaysia’s trusted relationship with Tehran.
“In some calls with Arab leaders, they’ve asked me to convey messages to the Iranian president because they know Malaysia’s relationship with Iran is good,” he said.
“We use positive approaches. We convey the concerns of Arab countries to Iran so that the tension will not prolong.”
This diplomatic back channel has already produced a tangible result.
Malaysia successfully persuaded Iran to allow seven Malaysian vessels four carrying crude oil to pass safely through the Strait of Hormuz without charge.
Iran’s ambassador to Malaysia confirmed the arrangement.
“Do you think it was easy to persuade the Iranian president to let our ships pass through the Strait of Hormuz?” Anwar told a party gathering in Johor on Sunday.
He attributed the breakthrough to Malaysia’s willingness to take a clear moral and diplomatic position on the conflict.
“Although Malaysia is not a large nation, we are grateful that all the Arab and Gulf countries involved have reached out to us, including the president of Iran.
We must be friends with everyone. Malaysia is a free and independent country, and we decide our own policies.”
Prof Geoffrey Williams of Williams Business Consultancy told TNS News that Malaysia’s diplomatic role reflects a structural advantage: a Muslim-majority country with deep Gulf ties, no military entanglement in the conflict, and strong economic relationships across both sides.
It is precisely this kind of neutral credibility that middle powers can deploy when great powers have exhausted their direct channels.
Shan Saeed, Global Chief Economist at Juwai IQI, has similarly argued that the crisis demonstrates how energy security and diplomatic capital are now inseparable policy priorities for ASEAN economies.
One Year of Liberation Day: The Tariff Architecture Holds -Barely
This week also marks one year since President Trump’s “Liberation Day” tariffs of 2 April 2025, which imposed some of the highest duties worldwide on ASEAN exporters including 49 percent on Cambodia and 46 percent on Vietnam.
Twelve months later, most ASEAN countries have negotiated bilateral deals with Washington that reduced tariffs to roughly 19–20 percent, often accompanied by sector-specific concessions.
Malaysia secured zero-tariff access for palm oil, pharmaceuticals, and aerospace components.
Vietnam agreed to eliminate several of its own tariffs.
In February 2026, the US Supreme Court ruled the tariffs unlawful under the International Emergency Economic Powers Act. However, they remain in force while further proceedings unfold.
Meanwhile, the Trump administration has launched Section 301 investigations into more than a dozen trading partners, opening the door to additional duties.
The verdict on Liberation Day for ASEAN remains mixed.
Exports from the region to the United States surged 23 percent year-on-year in late 2025, as global supply chains reconfigured around ASEAN’s lower tariff exposure relative to China.
Yet the Lowy Institute warns that ASEAN countries pursuing bilateral deals may have weakened the bloc’s collective negotiating leverage.
The unresolved 40 percent transshipment tariff threat targeting goods routed through ASEAN to circumvent China tariffs still hangs over the region’s manufacturing base like an undetonated charge.
The Iran War: A Tuesday Deadline and a Region Holding Its Breath
As this column goes to print, Trump’s Tuesday deadline has heightened anxiety across the region.
Iran remains defiant. The Islamic Revolutionary Guard Corps has declared the strait “decisively and dominantly” under Iranian control and insists it will not reopen the waterway until US and Israeli strikes cease.
A UN Security Council resolution sponsored by Bahrain to secure maritime passage was diluted under Russian and Chinese pressure to authorise only defensive measures limiting its practical impact.
Across Southeast Asia, emergency responses continue to multiply.
Thailand’s fuel prices have reached record highs, with unleaded gasoline at 57.51 baht per litre.
Indonesia has begun fuel rationing and ordered work-from-home arrangements for civil servants.
Vietnam has accelerated its E10 biofuel rollout to June 2026.
Singapore has established a special committee to manage supply disruptions and food price pressures.
The Philippines, the first country in the world to declare a national energy emergency following the Iran war on 24 March has begun sourcing Russian crude as an alternative supply.
Myanmar, already in civil war and still recovering from a 7.7-magnitude earthquake that killed 3,818 people, has imposed alternate-day private vehicle usage amid severe fuel shortages.
The IEA warns that April’s supply crunch will exceed March’s.
Bloomberg Economics modelling suggests the impact depends heavily on oil prices:
• USD110 per barrel: growth slowdown manageable
• USD170: stagflation risk roughly doubles
• USD200: emerging tail risk if the strait remains closed into May
For Southeast Asia, the window to avoid the most severe economic consequences is narrowing quickly.
What remains open for now is diplomacy.
And in that narrow space, Malaysia has demonstrated this week that size is not always the determining variable. – TNS NEWS
Tengku Noor Shamsiah Tengku Abdullah is Editor-in-Chief of TNS News and author of The Regional Lens, a weekly column examining the economic, political and geopolitical forces shaping Southeast Asia.