Jebb became the United Kingdom's Ambassador to the United Nations from 1950 to 1954 and to Paris from 1954 to 1960. He was the UK's first permanent UN representative. In the latter role, he was angered that secret negotiations between the British, French and Israelis in advance of the Suez invasion in 1956 took place at Sèvres without his knowledge and, in certain respects, that he was sidelined by Prime Minister Harold Macmillan at the Paris "big power" summit in 1960.