SECTION 1. Paragraph three, subsection (a) of section eleven of the Commonwealth Act numbered One Hundred eighty-six, as amended by the Republic Act Numbered Six hundred sixty, and further amended by Republic Act Numbered Seven hundred twenty-eight, is hereby further amended to read as follows:
"(3) For those who are at least sixty-five years of age, lump-sum payment of present value of annuity for first five years and annuity thereafter to be paid monthly; and for those who are at least sixty years of age and have rendered thirty-three years of service or more, the present value of the annuity for the first five years to be paid in five equal annual installments, each payable at the beginning of each year, and the annuity thereafter to be paid monthly; Provided, That said lump sum payment or annual installments of annuity may be made to retired employee only if the premiums paid by and for him are sufficient to cover said payment or payments: Provided, furher, That it shall be compulsory for an employer to pay on the date of retirement, in preference to all other obligations, except salaries and wages of its employees, its share of at least the premiums required to permit an employee to enjoy this option."