Harry L. Hopkins was Monnet's most important link to Roosevelt and to the administrative decision makers, for in 1941 Hopkins a former Secretary of Commerce moved into the White House as the President's key aide on the war. Hopkins took over from Morgenthau's Treasury Procurement Division the task of supplying arms to Britain, in this capacity he was Roosevelt's chief negotiator with Churchill. In 1943, Monnet left Washington for Algiers with the support of Hopkins and therefore with the approval of Roosevelt. Monnet's initial task was to keep Hopkins and the President informed on the split between Generals Giraud and de Gaulle and to try and reconcile their differences. Furthermore Monnet was to keep Robert Murphy, Roosevelt's representative in Algiers and Harold MacMillan, Churchill's representative, informed on US activities regarding North Africa. Later Monnet took on the role of handling supply and armament matters for the Comitè Francais de Liberation Nationale established after an agreement between Giraud and de Gaulle.

The originals are held in various Archives and Presidential Libraries in the USA