Iran’s military has again closed the Strait of Hormuz, just hours after briefly reopening the vital shipping lane, sending fresh shockwaves through global energy markets and maritime routes.
The reversal followed a short-lived easing of restrictions that allowed a number of commercial vessels to transit the waterway, which normally carries about a fifth of global oil and liquefied natural gas shipments. The reopening had initially raised hopes of stabilisation after a ceasefire linked to wider regional hostilities.
Maritime tracking data showed at least eight tankers passed through during the brief window, including crude oil, liquefied petroleum gas and chemical carriers. Some vessels were reportedly under US sanctions, while others displayed neutral routing signals linked to India or China in an apparent attempt to reduce risk exposure.
Several ships were also seen navigating close to Iranian territorial waters in line with precautionary guidance during heightened tension. However, Iranian state media later confirmed that “control of the Strait of Hormuz has returned to its previous status”, signalling a renewed closure and placing the waterway back under strict military oversight. The announcement underscored Tehran’s position that maritime access remains conditional amid geopolitical pressure.
The latest closure quickly reignited concern across shipping and energy markets, with operators reassessing whether transit through the strait could continue safely. Even brief disruptions in the narrow chokepoint have historically triggered volatility in freight costs and crude oil pricing due to its strategic importance in global supply chains.
Thailand’s PTT Plc confirmed that its tanker Serifos, carrying two million barrels of crude oil and stranded in the Gulf since March 7, was able to depart during the short opening period. The vessel is expected to arrive in Thailand on Tuesday, though the company cautioned that future shipments remain uncertain given the renewed closure.
Political analyst Wanwichit Boonprong, of Rangsit University, warned the latest move reflects a fragile and unpredictable security environment that could worsen without sustained diplomatic progress.
“It is unrealistic to expect Iran to surrender,” he said, adding Tehran appears prepared for prolonged confrontation and may continue using maritime pressure as leverage.
He said renewed escalation could extend beyond Hormuz, affecting other strategic routes including the Red Sea.
Mr Wanwichit described the reopening and closure as tactical manoeuvring rather than genuine de-escalation, suggesting global powers may now accelerate military positioning in anticipation of further instability.
He urged Thailand to move quickly to secure alternative oil supplies.
