The British considered producing an atomic bomb without American help, but it would require overwhelming priority, disruption to other wartime projects was inevitable, and it was unlikely to be ready in time to affect the outcome of the war in Europe. The unanimous response was that before embarking on this, another effort should be made to secure American cooperation. At the Quebec Conference in August 1943, Churchill and the President of the United States, Franklin Roosevelt, signed the Quebec Agreement, which merged the two national projects. The Quebec Agreement established the Combined Policy Committee and the Combined Development Trust to coordinate their efforts, and specified that the weapons could only be used if both the US and UK governments agreed. The 19 September 1944 Hyde Park Agreement extended both commercial and military cooperation into the post-war period.