UKMTO has been made aware of a suspicious approach 21nm south of Port Saleef in Yemen. Vessel was approached by two (2) small crafts, closest point of approach 50m port side. Weapons sighted on small craft, no shots were fired. 3-4 POB on each. Vessel increased speed and carried out maneuvers to evade small craft. Small craft has departed the vicinity. Master reported all vessel and crew safe.