Yemeni fighters from the Houthi movement said they will seal off Saudi Arabia’s coast starting Monday. Their spokesman, Yahya Saree, described it as maritime strike. Cargo vessels moving through the Red Sea near Saudi ports may encounter holdups. U.S. warplanes kept hitting targets after their warning. The group took several ships. Insurers now see Red Sea routes as dangerous. Traders are waiting anxiously, watching for extra costs or rerouted cargo. Saudi ports sit near the threatened zone, so any delay is critical quickly.