Quebec Agreement

The Quebec Agreement is an Anglo-Canadian-American document outlining the terms of coordinated development of the basic science and advanced engineering developments as related to nuclear energy; and, specifically weapons that employ nuclear energy. The joint agreement was between the United Kingdom and the United States, and signed by Winston Churchill and Franklin Delano Roosevelt on August 19, 1943, two years before the end of World War II, in Quebec City, Quebec, Canada.

The British Government was the first to realize that such an agreement was needed. On their own they had established beyond question that with their knowledge of the science of atomic energy, a nuclear weapon was both feasible and practicable. However by late 1941 they also realized that within the timeframe and scale of the then present war, the development of a useful nuclear weapon was completely beyond the manpower and material capability of both their country, and their Empire. Only the United States possessed the broad technology base in science and engineering, vast resources of skilled and semi-skilled manpower; and, an industrial infrastructure which could accept the burden of the development and production of nuclear weapons, concurrent with the meeting of the day-to-day production demands of the war. For this reason Winston Churchill's scientific and war mobilization advisors had advised him to seek the terms for setting up a British-American atomic-bomb project. In July 1943, in London, American officials cleared up some major misunderstandings about British motives, and the agreement was drafted.

After the signing, the United Kingdom handed over all of its material to the United States and, in return, received all the copies of the American progress reports to the president. The British atomic research was subsumed then into the Manhattan Project until after the war, and a large team of British and Canadian scientists moved to the United States.

In a section of the Quebec Agreement formally entitled "Articles of Agreement governing collaboration between the authorities of the USA and UK in the matter of Tube Alloys", the United Kingdom and the United States agreed to share resources "to bring the Tube Alloys project to fruition at the earliest moment."

The leaders also agreed as follows:

• "we will never use this agency against each other"
• "we will not use it against third parties without each other's consent"
• "we will not either of us communicate any information about Tube Alloys to third parties except by mutual consent"

The agreement also established a Combined Policy Committee composed of Canadian, British, and American representatives to oversee and coordinate weapons development. It was also agreed that "any post-war advantages of an industrial or commercial nature" would be decided at the discretion of the United States president. Although the document does not explicitly include "military" in "industrial or commercial", the subsequent view of the United States was to include "military" in the meaning, much to the displeasure of the United Kingdom.

One of the major strains of the Agreement came up in 1944, when it was revealed to the United States that the United Kingdom had earlier made a secret agreement with Hans von Halban to share nuclear information with France after the war in exchange for free use of a number of patents related to nuclear reactors and filed by Frédéric Joliot-Curie and his Collège de France team. Upon this revelation, the United States objected, stating that the Halban agreement violated the terms of the Quebec Agreement, namely the section about the third-party information-sharing without prior mutual consent. At Churchill's urging, the United Kingdom broke its obligations to France in order to satisfy the United States.

After the war, the United Kingdom was unilaterally excluded from American nuclear research by the McMahon Act, and so created its own atomic-bomb program, but with much information from the joint work on the Manhattan Project.

The Hyde Park Agreement was also entered into by Roosevelt and Churchill when Churchill saw Roosevelt at Hyde Park on 17 & 18 September 1944. This provided for Full collaboration between the United States and the British Government in developing Tube Alloys (the British code name for the bomb project) for military and commercial purposes should continue after the defeat of Japan unless and until terminated by joint agreement" However "This agreement was improperly filed at Hyde Park under “Tube Alloys” and so did not become known to Stimson or General Marshall until after the war, when the United Kingdom furnished a copy. Even then, Groves questioned the document’s authenticity until the United States' copy was located."