The three Foreign Ministers of the Benelux met in The Hague on 23 April 1955. Based on the Beyen memorandum and a memorandum of Jean Monnet on nuclear energy they drafted a joint memorandum to present to their colleagues of the European Coal and Steel Community (ECSC). They finalized the memorandum on 18 May 1955 and presented it to the governments of France, Germany and Italy on 20 May 1955. They proposed to hold an intergovernmental conference to prepare integration in the fields mentioned in the memorandum, and to discuss the way towards a general integration of the European economy.
Summary
In the memorandum the Benelux proposed the establishment of an Economic Community based on a general common market and a sectoral approach for transport and energy, especially nuclear energy (the last was in the line of the approach taken with the ECSC). The common market was to be achieved by a gradual reduction of trade restriction and custom tariffs. Besides the economic domain the memorandum proposed an integration also at the social and financial domain. In addition they proposed the creation of a joint (supranational) independent authority.
Outcome
The Common Assembly of the European Coal and Steel Community assembled on 14 May 1955 decided that at the Messina Conference to be held later that month they would discuss the way to move forward towards European integration.
The Beyen Plan on CVCE website (Centre for European Studies).
Raymond F. Mikesell, The Lessons of Benelux and the European Coal and Steel Community for the European Economic Community, The American Economic Review, Vol. 48, No. 2, Papers and Proceedings of the Seventieth Annual Meeting of the American Economic Association (May, 1958), pp. 428–441