Amr retired from squash in 1938 while still the top player in the game in order to pursue his career as a diplomat. He served as Egypt's ambassador to the United Kingdom from 1945 to 1952. At the time, King Farouk of Egypt was eager to improve Egypt's relations with the United Kingdom. Since Amr was known to be on good terms with the British authorities, the king appointed him on 11 November 1944 as minister plenipotentiary at the Egyptian Embassy in London, where Amr had previously held the post of honorary counselor. Amr replaced Hassan Pasha Nashaat, who was removed from his position after marrying a non-Egyptian. Amr was promoted to the rank of ambassador in August 1945, and always tried to influence King Farouk's decisions in favour of British interests. This led famed intellectual Taha Hussein to state that Amr was "more suited to be Britain's ambassador in Egypt than Egypt's ambassador in Britain."