On 1 February 1941, Philip was commissioned as a sub-lieutenant after a series of courses at Portsmouth, in which he gained the top grade in four out of five sections of the qualifying examination. Among other engagements, he was involved in the Battle of Crete and was mentioned in dispatches for his service during the Battle of Cape Matapan, in which he controlled the battleship's searchlights. He was also awarded the Greek War Cross. In June 1942, he was appointed to the destroyer , which was involved in convoy escort tasks on the east coast of Britain, as well as the Allied invasion of Sicily.
