On 13 May 1957, Jean Monnet, President of the Action Committee for the United States of Europe (ACUSE), sends a letter to Cornelius Wilhelmus van Wingerden, Chairman of the Dutch Trade Union Federation and member of ACUSE, in which he calls for the prompt ratification of the Treaties establishing the European Economic Community (EEC) and the European Atomic Energy Community (EAEC or Euratom), signed on 25 March 1957 in Rome by the representatives of the six Member States of the European Coal and Steel Community (ECSC).