22 U.S.C. § 2680–1

(a) In general An officer or employee of the Department of State to whom a written or oral question is addressed by any member of a committee specified in subsection (b), acting within his official capacity, shall respond to such question within 21 days unless the Secretary of State submits a letter to such member explaining why a timely response cannot be made. (b) Specified committees The committees referred to in subsection (a) are the Committee on Foreign Relations of the Senate and the Committee on Foreign Affairs of the House of Representatives.