Trump Extends US–Iran Ceasefire Indefinitely; IRGC Seizes Vessels; US Issues 3–5 Day Ultimatum

In a major diplomatic pivot announced on Truth Social on April 21 and taking effect April 22, President Trump extended the US–Iran ceasefire indefinitely — contingent on Iran submitting a 'unified proposal' for ending the nuclear standoff. The extension, made at Pakistan's request, forestalled an expected US military resumption but did not end coercive pressure. On April 22, Iran's Islamic Revolutionary Guard Corps (IRGC) seized two vessels in the Strait of Hormuz, which Al Jazeera's live blog confirmed, in apparent retaliation for the continuing US naval blockade. US officials simultaneously issued Iran a 3-to-5 day window to resolve internal factional divisions and begin substantive negotiations, warning strikes would resume if Iran failed to engage. Iranian Foreign Minister Abbas Araghchi condemned the ongoing blockade as 'an act of war.' An Iranian parliamentary adviser characterized the extension as 'a ploy to buy time for military escalation.' The core nuclear sticking point crystallized publicly: the US is demanding a 20-year pause on uranium enrichment, while Iran has offered only 5 years. The episode represents the continuation of what analysts have called structural coercive diplomacy: each party using the ceasefire to extract concessions rather than genuinely converge toward a framework agreement.