22 USC 2423 - Exchanges of certain materials

(a) Agreement for necessary or strategic raw material; definition 
Notwithstanding any other provision of law, whenever the President determines it is in the United States national interest, he shall furnish assistance under this chapter or shall furnish defense articles or services under the Foreign Military Sales Act [22 U.S.C. 2751 et. seq.], pursuant to an agreement with the recipient of such assistance, articles, or services which provides that such recipient may only obtain such assistance, articles, or services in exchange for any necessary or strategic raw material controlled by such recipient. For the purposes of this section, the term necessary or strategic raw material includes petroleum, other fossil fuels, metals, minerals, or any other natural substance which the President determines is in short supply in the United States.
(b) Allocation of raw materials to Federal agencies 
The President shall allocate any necessary or strategic raw material transferred to the United States under this section to any appropriate agency of the United States Government for stockpiling, sale, transfer, disposal, or any other purpose authorized by law.
(c) Deposits in United States Treasury of funds from disposal of materials 
Funds received from any disposal of materials under subsection (b) of this section shall be deposited as miscellaneous receipts in the United States Treasury.