Yemeni fighters from the Houthi movement said they will close Saudi Arabia’s coast starting Monday. Their spokesman, Yahya Saree, described it as naval attack. Merchant ships moving through the Red Sea near Saudi ports could face delays. U.S. warplanes kept hitting objectives after their warning. The group captured several ships. Insurers now see Red Sea routes as dangerous. Traders are watching closely, watching for additional charges or diverted shipments. Saudi ports sit near the threatened zone, so any slowdown matters fast.