Robert Nathan was an important new-deal economist in the Roosevelt administration. Before the fall of France in 1940 he had worked in the Department of Commerce and then in National Defense Advisory Commission. It was at this time that his contact with Monnet, who was procuring arms for the British, began. According to Nathan, Monnet was primarily responsible for increasing the production requirements from the military branches to help Europe defend itself, and for Monnet, Robert Nathan was the key to achieving these mobilisation targets in the US. Nathan was also involved in the lend-lease negotiations in 1945, where Monnet was told that any further aid would be dependent upon the French drawing up a precise programme to restore its economy. This provided the impetus for the French National Modernisation Plan or the Monnet Plan, as it is more commonly known. Monnet sought the advice of Nathan in drafting the plan, aware of his skill in analysing data and statistics, Nathan spent a month in Paris in August 1946, working on re-drafting the plan. He emphasised the importance of having realistic objectives and goals, in compensating for the shortage of manpower and the need to achieve public consensus by organising a publicity campaign promoting the national recovery programme. He also asked Monnet if he could work with the plan organisers in 1947, in procuring loans for its implementation.

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