Britain sent a representative to the Messina Conference in June 1955, but withdrew. The British proposed a Free Trade Area around the customs union of the European Economic Community (EEC), but this was rejected. The 'Inner Six' (France, West Germany, Italy and the three Benelux countries: Belgium, the Netherlands and Luxembourg) signed the Treaty of Rome in March 1957, establishing the European Atomic Energy Community (Euratom). The EEC was inaugurated in 1958.
Britain joined the Organisation for European Economic Co-operation (OEEC) in 1961 and worked towards the reduction of trade restrictions between members. Britain was suspicious of the French Schumann plan to establish a supranational body regulating the production and sale of coal and steel.
In 1959 Britain signed the Stockholm Convention with other non-EEC European states (Austria, Denmark, Norway, Portugal, Sweden and Switzerland) and created the European Free Trade Association (EFTA). However, EFTA was no competitor for the EEC and was ineffective in establishing a useful free trade area.
The Prime Minister, Harold Macmillan, was alarmed at the rapid economic advances made by France and Germany and sought to join the EEC. Britain's commonwealth ties, domestic agricultural policy, and close links to the US were obstacles in joining and the French President, Charles de Gaulle, vetoed Britain's application in 1963. The Wilson government again failed to take Britain into the EEC in 1967 but Georges Pompidou, who succeeded de Gaulle, finally relented and Britain joined in January 1973 under the premiership of Edward Heath.
The 1974 Wilson government was unhappy with the terms of EEC membership and held a referendum in June 1975. A substantial majority voted in favour of continued membership although Britain consistently resisted supranational industrial, scientific and social policies.