Iran closed the Strait of Hormuz again on April 18, 2026, and fired on a tanker attempting to pass through, escalating the standoff over the critical shipping lane in response to the ongoing US blockade of Iranian ports. The closure threatens global oil supplies and comes as part of the broader US-Israel war on Iran that began in late February 2026. Multiple outlets confirm the gunfire incident and closure; the key uncertainty is how long Iran will sustain the blockade and whether the US will respond militarily or diplomatically to lift its own port restrictions.