22 CFR § 50.50 - Renunciation of nationality.
(a) A person desiring to renounce U.S. nationality under section 349(a)(5) of the Immigration and Nationality Act shall appear before a diplomatic or consular officer of the United States in the manner and form prescribed by the Department. The renunciant must include on the form he signs a statement that he absolutely and entirely renounces his U.S. nationality together with all rights and privileges and all duties of allegiance and fidelity thereunto pertaining.
(b) The diplomatic or consular officer shall forward to the Department for approval the oath of renunciation together with a certificate of loss of nationality as provided by section 358 of the Immigration and Nationality Act. If the officer's report is approved by the Department, copies of the certificate shall be forwarded to the Immigration and Naturalization Service, Department of Justice, and to the person to whom it relates or his representative.