On April 12, 2026, the U.S. Central Command announced that the U.S. military will implement a blockade of all Iranian ports starting Monday at 10 a.m. ET, following the failure of peace talks between the United States and Iran over the weekend [1]. President Donald Trump stated that he ordered the Navy to interdict any ship in international waters that has paid Iran a toll to transit the Strait of Hormuz, a critical route for global oil shipments [1]. The blockade will be enforced impartially against vessels of all nations entering or departing Iranian ports and coastal areas, including all Iranian ports on the Arabian Gulf and Gulf of Oman, according to CENTCOM [1]. However, vessels transiting to and from non-Iranian ports will not be impeded [1].
The announcement triggered a sharp surge in oil prices. U.S. crude oil futures for May delivery jumped 8% to $104.40 per barrel by 6:01 p.m. ET, while international benchmark Brent for June delivery advanced more than 7% to $102.51 [1]. Tanker traffic through the Strait of Hormuz has plunged due to the threat of Iranian attacks, causing what is described as the largest oil supply disruption in history. Before the conflict escalated, about 20% of global oil supplies passed through the waterway [1]. Since the U.S. and Israel attacked Iran on February 28, traffic has dropped significantly, with only three supertankers making the journey on Saturday compared to more than 100 vessels daily before the war [1].
President Trump had previously threatened to blockade the Strait of Hormuz after failed negotiations in Pakistan and indicated that the Navy would begin blockading any ships attempting to enter or leave the strait [1]. He also mentioned the possibility of resuming airstrikes on Iran, though it remains unclear if this will occur [1]. The president agreed to a two-week ceasefire on Tuesday in exchange for Tehran allowing ships to pass through the strait, but Tehran has made safe passage contingent on its approval [1]. Ali Akbar Velayati, a senior advisor to Iran's Supreme Leader Mojtaba Khamenei, asserted that the "key to the Strait of Hormuz" remains in Iran's hands [1].
Market participants are reacting to the heightened geopolitical risk and supply disruption, with oil prices spiking and tanker traffic remaining well below pre-war levels [1].
CONCLUSION
The U.S. Navy's impending blockade of Iranian ports has caused oil prices to surge above $100 per barrel, reflecting significant market anxiety over supply disruptions. With tanker traffic through the Strait of Hormuz at historic lows and uncertainty about further military escalation, the oil market faces heightened volatility and risk. The situation remains fluid, with both U.S. and Iranian officials emphasizing their control over the critical waterway.