The idea, which was first proposed by the anglophile French Prime Minister, Guy Mollet in September 1956, was rejected by Britain’s Prime Minister, Anthony Eden.
At the time it was made the Suez crisis was escalating, the French ecomony was in a mess and Britain was seen as a social and economic role model in Paris. Previously secret cabinet papers reveal that two weeks later Mollet made another request.
This time to join the British Commonwealth, a move which would have made Queen Elizabeth the official head of state of republican France. This too was rejected by Eden and a year later France signed the Treaty of Rome with Germany and the other founding nations of the Common market.