22 U.S.C. § 4067 — Compatibility between retirement systems

In order to maintain existing conformity between the Civil Service Retirement and Disability System under subchapter III of chapter 83 of title 5, and the Foreign Service Retirement and Disability System, whenever a law of general applicability is enacted which—

such law shall be extended in accordance with subsection (b) to the Foreign Service Retirement and Disability System so that it applies in like manner with respect to participants, former participants, annuitants, or survivors under that System.

The President shall by Executive order prescribe regulations to implement this section and may make such extension retroactive to a date no earlier than the effective date of the provision of law applicable to the Civil Service Retirement and Disability System. Any provision of an Executive order issued under this section shall modify, supersede, or render inapplicable, as the case may be, to the extent inconsistent therewith—

The President shall maintain, under the same conditions and in the same manner as provided in subsections (a) and (b) existing conformity between the Federal Employees’ Retirement System provided in chapter 84 of title 5 and the Foreign Service Pension System provided in part II of this subchapter.