The 1973 Constitution of the Republic of the Philippines

Section 1

1. Any amendment to, or revision of, this Constitution may be proposed by the National Assembly upon a vote of three-fourths of all its Members, or by a constitutional convention. 2. The National Assembly may, by a vote of two-thirds of all its Members, call a constitutional convention, or by a majority vote of all its Members, submit the question of calling such a convention to the electorate in an election.

Section 2

Any amendment to or revision of this Constitution shall be valid when ratified by a majority of the votes cast in the plebiscite which shall be held not later than three months after the approval of such amendment or revision.