Strategic and other materials acquired by the Commodity Credit Corporation as a result of barter or exchange of agricultural commodities or products, unless acquired for the national stockpile established pursuant to the Strategic and Critical Materials Stock Piling Act [50 U.S.C. 98 et seq.], or for other purposes shall be transferred to the supplemental stockpile established by section 1704(b) ^[1] of this title; but no strategic or critical material shall be acquired by the Commodity Credit Corporation as a result of such barter or exchange except for such national stockpile, for such supplemental stockpile, for foreign economic or military aid or assistance programs, or for offshore construction programs, or to meet requirements of Government agencies.