The IRGC warned it has prepared for a "long-term war" with unused strategic weapons, while Trump told Fox News he was weighing options "if and when do I blow the entire nation up."
A senior Houthi official said Washington reached out after the group's advance to Bab el-Mandeb, as US media reported Trump cancelled planned strikes at the last minute after a call with Crown Prince Mohammed bin Salman.
The alerts advised Americans to "be aware of potential flight cancellations, airspace closures, and travel disruptions" and said the conflict could "escalate rapidly."
The pipeline disruption comes as Gulf oil exports have already fallen sharply and shipping routes face further threats. With no restart date announced, the impact on deliveries to Europe and Asia depends on how long the shutdown lasts.