The Director shall prescribe regulations under which a previous spouse who is divorced after September 29, 1988, from a participant, former participant, or retired participant shall be eligible for a survivor annuity to the same extent and, to the greatest extent practicable, under the same conditions (including reductions to be made in the annuity of the participant) applicable to former spouses (as defined in section
8331
(23) of title
5) of participants in the Civil Service Retirement and Disability System (CSRS) as prescribed by the Civil Service Retirement Spouse Equity Act of 1984.