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22 U.S. Code § 290g–3 - Specific actions requiring Congressional authorization

Unless Congress by law authorizes such action, neither the President nor any person or agency shall, on behalf of the United States:
(a)
agree to an increase in the subscription of the United States to the Fund;
(b)
vote for or agree to any amendment of the agreement which increases the obligations of the United States, or which would change the purpose or functions of the Fund; or
(c)
make a loan or provide other financing to the Fund, except that funds for technical assistance may be provided to the Fund by a United States agency created pursuant to an Act of Congress which is authorized by law to provide funds to international organizations.