power. They signed a Memorandum of Intention that replaced the Quebec Agreement. It made Canada a full partner, and reduced the obligation to obtain consent for the use of nuclear weapons to merely requiring consultation. The three leaders agreed that there would be full and effective cooperation on civil and military applications of atomic energy, but the British were soon disappointed; the Americans made it clear that cooperation was restricted to basic scientific research. The Atomic Energy Act of 1946 (McMahon Act) ended technical cooperation. Its control of "restricted data" prevented the United States' allies from receiving any information. Attlee set up a cabinet sub-committee, the Gen 75 Committee (known informally as the "Atomic Bomb Committee"), on 10 August 1945 to examine the feasibility of a nuclear weapons program. In October 1945, it accepted a recommendation that responsibility be placed within the Ministry of Supply. The Tube Alloys Directorate was transferred from the Department of Scientific and Industrial Research to the Ministry of Supply on 1 November 1945. To coordinate the effort, Lord Portal, the wartime Chief of the Air Staff, was appointed Controller of Production, Atomic Energy (CPAE), with direct access to the Prime Minister. An Atomic Energy Research Establishment (AERE) was established at RAF Harwell, south of Oxford, under the directorship of Cockcroft. AERE moved to Aldermaston in 1952. Christopher Hinton agreed to oversee the design, construction and operation of the new atomic weapons facilities. These included a new uranium plant at Springfields in Lancashire, and nuclear reactors and plutonium processing facilities at Windscale in Cumbria. Hinton established his headquarters in a former Royal Ordnance Factory at Risley in Lancashire on 4 February 1946. In July 1946, the Chiefs of Staff Committee recommended that Britain acquire nuclear weapons. They estimated that 200 bombs would be required by 1957. Despite this, and the research and construction of production facilities that had already been approved, there was still no official decision to proceed with making atomic bombs. Portal submitted a proposal to do so at the 8 January 1947 meeting of the Gen 163 Committee, a subcommittee of the Gen 75 Committee, which agreed to proceed with the development of atomic bombs. It also endorsed his proposal to place Penney, now the Chief Superintendent Armament Research (CSAR) at Fort Halstead in Kent, in charge of the bomb development effort, which was codenamed High Explosive Research. Penney contended that "the discriminative