On 20 January 1966, in Strasbourg, participating in an exchange of views between the Community institutions on the empty chair crisis, Paul-Henri Spaak, Belgian Foreign Minister, outlines Belgium’s position in this affair and takes into account the efforts made on 17 and 18 January in Luxembourg by the Foreign Ministers of the Six to resolve the crisis.

Dans ses Mémoires, Paul-Henri Spaak, ancien ministre belge des Affaires étrangères, pointe les origines politiques et institutionnelles de la crise de la chaise vide de 1965 et décrit le déroulement des négociations diplomatiques ayant permis, le 29 janvier 1966 à Luxembourg, d'atteindre un compromis politique pour mettre fin à la crise communautaire.

On 18 September 1954, Paul-Henri Spaak, Belgian Foreign Minister, gives an address to the Consultative Assembly of the Council of Europe in which he deplores the persistent disputes between France and Germany which led the French National Assembly to reject the Treaty of the European Defence Community (EDC) a few days earlier.

Le 19 janvier 1945, Jules Guillaume, ambassadeur de Belgique à Paris transmet une lettre à Paul-Henri Spaak, ministre belge des Affaires étrangères, dans laquelle il évoque la position de la France quant à la création d'une union douanière entre la Belgique, la France, le Luxembourg et les Pays-Bas.

On 20 October 1948, Raoul de Fraiteur, Belgian Defence Minister, sends a confidential letter to Paul-Henri Spaak, Belgian Prime Minister and Foreign Minister, in which he reviews the decisions adopted by the conference of defence ministers of the five Member States of Western Union.

In this note, Paul-Henri Spaak, Belgian Foreign Minister, informs Émile de Cartier de Marchienne, Belgian Ambassador to London, of the principles and the conditions relating to Belgium’s participation in the Allied military occupation of Germany.

In this letter, Belgian Foreign Minister Paul-Henri Spaak assures the US Government of Belgium's formal support for the United Nations Relief and Rehabilitation Administration (UNRRA) project, but suggests some adaptations given the country's situation.

In this letter sent to the Belgian Foreign Minister, Paul-Henri Spaak, on 3 December 1954, Robert Silvercruys, the Belgian Ambassador to the United States, considers the mindset of US officials following the failure of the European Defence Community (EDC) project.

In this note sent to the Belgian Foreign Minister, Paul-Henri Spaak, on 30 October 1954, Robert Silvercruys, Belgian Ambassador to the United States, tells of the satisfaction in the United States that greeted the signing, on 23 October 1954, of the Paris Agreements establishing Western European Union (WEU).

On 4 April 1955, following the failure of the European Defence Community (EDC), Johan Willem Beyen, Netherlands Foreign Minister, forwards to his Belgian and Luxembourgish counterparts, Paul-Henri Spaak and Joseph Bech, a memorandum in which he proposes the revival of European integration through general, rather than sectoral, economic integration as part of a common market.