22 U.S.C. § 3942: Appointments by the President

The President may, by and with the advice and consent of the Senate, appoint an individual as a chief of mission, as an ambassador at large, as an ambassador, as a minister, as a career member of the Senior Foreign Service, or as a Foreign Service officer. The President may, by and with the advice and consent of the Senate, confer the personal rank of career ambassador upon a career member of the Senior Foreign Service in recognition of especially distinguished service over a sustained period. Subject to the requirement of clause (ii), the President may confer the personal rank of ambassador or minister on an individual in connection with a special mission for the President of a temporary nature not exceeding six months in duration. the necessity for conferring such rank, the dates during which such rank will be held, the justification for not submitting the proposed conferral of personal rank to the Senate as a nomination for advice and consent to appointment, and all relevant information concerning any potential conflict of interest which the proposed recipient of such personal rank may have with regard to the special mission. An individual upon whom a personal rank is conferred under subparagraph (A) or (B) shall not receive any additional compensation solely by virtue of such personal rank. Except as provided in paragraph (2)(B) of this subsection or in clause 3, section 2, article II of the Constitution (relating to recess appointments), an individual may not be designated as ambassador or minister, or be designated to serve in any position with the title of ambassador or minister, without the advice and consent of the Senate. If a member of the Service is appointed to any position in the executive branch by the President, by and with the advice and consent of the Senate, or by the President alone, the period of service in that position by the member shall be regarded as an assignment under subchapter V and the member shall not, by virtue of the acceptance of such assignment, lose his or her status as a member of the Service. A member of the Senior Foreign Service who accepts such an assignment may elect to continue to receive the salary of his or her salary class, to remain eligible for performance pay under subchapter IV, and to receive the leave to which such member is entitled under subchapter I of chapter 63, title 5, as a member of the Senior Foreign Service, in lieu of receiving the salary and leave (if any) of the position to which the member is appointed by the President.