On 11 May 1956, basing its actions on the Spaak Report, the Common Assembly of the European Coal and Steel Community (ECSC) adopts a resolution in which it sets out its wishes with regard to the establishment of a Common Market and Euratom.
On 16 March 1956, the Common Assembly of the European Coal and Steel Community (ECSC) adopts a resolution urging the six Member States of the ECSC to draft and to adopt a Treaty establishing a general Common Market in the form of a customs union.
On 13 February 1957, during its debates on the Common Market and Euratom, the Common Assembly of the European Coal and Steel Community (ECSC) adopts a resolution in which it emphasises the importance of establishing a European supranational executive body and of rationalising relations between the institutions of the European Communities.
On 30 November 1954, Jean Monnet, President of the High Authority, gives an initial assessment of the activities of the European Coal and Steel Community (ECSC) to the Common Assembly meeting in extraordinary session.
On 11 May 1956, Paul-Henri Spaak, Belgian Foreign Minister and Chairman of the Intergovernmental Committee established by the Messina Conference, attends the debates of the Common Assembly of the European Coal and Steel Community (ECSC) on the Spaak Report and responds, in particular, to the criticisms of the French delegate, Michel Debré.
On 14 May 1955, the Common Assembly of the European Coal and Steel Community (ECSC) adopts a resolution setting out its position and its demands in preparation for the Messina Conference, to be held from 1 to 3 June 1955.
On 7 January 1957, on the margins of the diplomatic negotiations being conducted at the Château de Val Duchesse, the working party of the Common Assembly of the European Coal and Steel Community (ECSC) draws up a memorandum on the progress of European revival and comments on the Euratom and Common Market projects.