22 USC 4309 - Application to public international organizations and official missions to such organizations

(a) Determination by Secretary 
The Secretary may make section 4306 of this title, or any other provision of this chapter, applicable with respect to an international organization to the same extent that it is applicable with respect to a foreign mission if the Secretary determines that such application is necessary to carry out the policy set forth in section 4301 (b) of this title and to further the objectives set forth in section 4304 (b) of this title.
(b) “International organization” defined 
For purposes of this section, international organization means
(1) a public international organization designated as such pursuant to the International Organizations Immunities Act (22 U.S.C. 288288f2) or a public international organization created pursuant to a treaty or other international agreement as an instrument through or by which two or more foreign governments engage in some aspect of their conduct of international affairs; and
(2) an official mission (other than a United States mission) to such a public international organization,

including any real property of such an organization or mission and including the personnel of such an organization or mission.