Brussels and the European Union a provisional seat, though with the Common Assembly in Strasbourg as that was the only city with a large enough hemicycle (the one used by the Council of Europe). This agreement was temporary, and plans were set to relocate the institutions to Saarbrücken which would serve as a "European District", but this did not occur. The 1957 Treaties of Rome established two new communities, the European Economic Community (EEC) and the European Atomic Energy Community (Euratom). These shared the Assembly and Court of the ECSC but created two new sets of Councils and Commissions (equivalent to the ECSC's High Authority).
Treaty establishing the European Defence Community 1952, with French support. The new EDC treaty was signed on 27 May 1952. Although with some doubts and hesitation, the United States and the six members of the European Community approved the Pleven Plan. This led the way to the Paris Conference, launched in February 1951, where it was negotiated the structure of the supranational army. Among compromises and differences, on 27 May 1952 the six foreign ministers signed the Treaty of Paris establishing the European Defence Community (EDC). Despite the central role for France, the EDC plan collapsed when it failed to obtain ratification in the French Parliament.