A series of proclamations were issued under this and other contingent emergency statutes in September 1939.[327] The prohibition on export of war material was narrowed to a prohibition on the export of such material until title had unconditionally passed to the foreign purchaser--the cash and carry system.[328] A number of Presidential proclamations effected application of the new statute.[329] Presidential proclamations also reflect the change in emphasis of statutory prohibitions of the export of war materials. In September 1939, the President issued a clearly neutrality-oriented proclamation prohibiting enlistment in, or recruitment for, belligerent armed forces, provisioning of belligerent ships,[330] and subsequent proclamations of 1940 and 1941 were equally clearly concerned with preserving adequate domestic stocks of strategic materials.[331] Upon amendment of the July 1940[332] Act in June 1942, the President was authorized to prohibit or curtail the exportation of any articles, technical data, materials, or supplies, except under such rules and regulations as he might prescribe.[333] Unless the President otherwise directed, the functions and duties of the President under this section of the Act were to be performed by the Board of Economic Warfare.[334] The Export Control Act of 1949 empowered the President to prohibit or curtail the exportation from the United States, its Territories and possessions, of any articles, materials, or supplies, including technical data but excluding agricultural commodities in excess of domestic requirements.[335] The purpose here was to protect the United States from the excessive drain of scarce materials.[336] The Atomic Energy Act also prohibited the export from or import into the United States or curtail the exportation from the United States, its Territories and as authorized by the Atomic Energy Commission upon a determination by the President that the common defense and security would not be adversely affected thereby.[337] Obviously embraced within the power to embargo is the power conditionally to permit exports. Thus, in December 1941 following Pearl Harbor, Congress permitted the President, whenever he deemed it to be in the interest of national defense, to authorize the Secretary of War to sell, transfer title to, exchange, lease, lend, or otherwise dispose of, to the government of any country whose defense the President deemed vital to the defense of the United States, any defense article procured from funds appropriated for the military establishment prior to or since March 11, 1941.[338]