Saudi Arabia declared its national security a “red line” after a coalition strike targeted vehicles and cargo in Yemen allegedly supplied by the UAE to southern separatists.

The limited military operation at Mukalla port came after warnings to the Southern Transitional Council (STC) against military action in Hadramout province.

Yemen’s Saudi-backed presidential council demanded all UAE forces leave within 24 hours, canceled a joint defense agreement, imposed a 72-hour blockade, and declared a 90-day state of emergency.

The strike targeted weapons and combat vehicles unloaded from two ships, with no casualties or collateral damage reported, Al-Jazeera has reported.

The move follows heightened tensions after an STC offensive, prompting calls for diplomacy from U.S. officials amid ongoing regional friction.