8 C.F.R. § 343b.1
A naturalized citizen who desires to obtain recognition as a citizen of the United States by a foreign state shall submit an application on the form designated by USCIS with the fee specified in 8 CFR 106.2 and in accordance with the form instructions. He shall not be furnished with verification of his naturalization for such purpose in any other way. An applicant who is a claimant against a foreign government for property damage pursuant to the provisions of a peace treaty shall not be requested to furnish the name, official title, and address of a foreign official unless such information is available when the investigation of the applicant is conducted. The applicant shall be required to appear in person before an assigned officer for interrogation under oath or affirmation upon the application.
8 C.F.R. §343b.1