Brent Crude Falls 10%+ as Iran Opens Hormuz — Trump's Conditional Blockade Adds Uncertainty

Global oil prices plunged more than 10% over April 17-18, 2026 following Iran's declaration that the Strait of Hormuz is 'completely open' to commercial shipping. The drop erased much of the spike triggered by Trump's April 12 blockade announcement. However, Trump's statement that the US naval blockade 'will remain in full force' until a comprehensive peace deal, combined with Iran's characterization of the re-opening as subject to 'strict management and control,' introduced uncertainty about whether the Hormuz supply disruption is truly resolved. Markets are watching the April 22 ceasefire renewal deadline as a critical inflection point. Hormuz carries 20-21% of global daily oil supply.