A participant who, while on approved leave without pay, serves as a full-time paid employee of a Member or office of the Congress shall continue to make contributions to the Fund based upon the Foreign Service salary rate that would be in effect if the participant were in a pay status. The participant’s employing Member or office in the Congress shall make a contribution (from the appropriation or fund which is used for payment of the salary of the participant) determined under section
4071f
(a) of this title to the Treasury of the United States to the credit of the Fund. All periods of service for which full contributions to the Fund are made under this subsection shall be counted as creditable service for purposes of this part and shall not, unless all retirement credit is transferred, be counted as creditable service under any other Government retirement system.