For National Defense Sealift Fund programs, projects, and activities, and for expenses of the National Defense Reserve Fleet, as established by section 11 of the Merchant Ship Sales Act of 1946 (50 U.S.C. App. 1744), and for the necessary expenses to maintain and preserve a U.S.-flag merchant fleet to serve the national security needs of the United States, $1,349,094,000, to remain available until expended:
Provided, That none of the funds provided in this paragraph shall be used to award a new contract that provides for the acquisition of any of the following major components unless such components are manufactured in the United States: auxiliary equipment, including pumps, for all shipboard services; propulsion system components (that is; engines, reduction gears, and propellers); shipboard cranes; and spreaders for shipboard cranes:
Provided further, That the exercise of an option in a contract awarded through the obligation of previously appropriated funds shall not be considered to be the award of a new contract:
Provided further, That the Secretary of the military department responsible for such procurement may waive the restrictions in the first proviso on a case-by-case basis by certifying in writing to the Committees on Appropriations of the House of Representatives and the Senate that adequate domestic supplies are not available to meet Department of Defense requirements on a timely basis and that such an acquisition must be made in order to acquire capability for national security purposes.