(1) Pursuant to paragraph 2(b) of Annex C to the Agreement in Implementation of Article IV of the Panama Canal Treaty of 1977, the President, or the Presidents designee, shall purchase from a source determined by the President to be appropriate, in accordance with such regulations as the President or the Presidents designee may prescribe, and to such extent or in such amounts as may be provided in advance in appropriation Acts, a nontransferable deferred annuity for the benefit of each employee of an agency or instrumentality of the Government of the United States in the Republic of Panama
(A) who is not a citizen of the United States;
(B) who was employed on October 1, 1979, and during any period before that date by an agency or instrumentality of the Government of the United States at any permanent duty station in the Republic of Panama (including, with respect to employment before that date, the area then known as the Canal Zone);
(C) who, for any period of service with such agency or instrumentality before October 1, 1979, at any such permanent duty station was not covered, by reason of that service, by the United States Civil Service Retirement system or any other Federal retirement system providing benefits similar to those retirement benefits provided by the Social Security System of the Republic of Panama; and
(D) who, on October 1, 1979, is under a Federal retirement system and, on or before that date, has accrued in one or more agencies or instrumentalities of the United States a total of 5 years or more of service which
(i) is creditable toward any Federal retirement system as in effect on October 1, 1979;
(ii) would have been creditable toward any such retirement system if the retirement system were in effect at the time of the service accrued by the employee; or
(iii) consists of any combination of service described in clauses (i) and (ii) of this subparagraph.