A Tanker underway in the Red Sea was approached by up to seven persons aboard a high-speed craft flying a white flag. The craft closed to within 0.8NM of the vessel before the crew sounded the alarm and mustered. No weapons were observed on the approaching craft. The tanker's crew displayed gun-like objects on the vessel's railings as a deterrent measure. Upon observing these defensive displays, the suspicious craft abandoned its approach. The Tanker continued its transit without requiring assistance.