De Cruz was born in the United Kingdom on 2 February 1954 to Gerald Evelyn de Cruz and Coral Alma Phipps.[2] His elder sister is Justice Judith Prakash.[3] He also has one younger half-brother, Adam.[2]
In 1996, he was appointed as Singapore's Ambassador to the Philippines,[5] a position he held until 1999,[1] when he was appointed as the Ambassador of Singapore to Myanmar in 2000 and held that position until 2004.[1][4]
After serving in a department of the Ministry of Foreign Affairs, he was appointed as Singapore's High Commissioner to Papua New Guinea on 29 May 2006.[1]