Dissolution and issue of proclamations by President
Section 64 · 1999 Constitution (2004 edition)
What Constitution says
(1) The Senate and the House of Representatives shall each stand dissolved at the expiration of a period of four years commencing from the date of the first sitting of the House. (2) If the Federation is at war in which the territory of Nigeria is physically involved and the President considers that it is not practicable to hold elections, the National Assembly may by resolution extend the period of four years mentioned in subsection (1) of this section from time to time but not beyond a period of six months at any one time. (3) Subject to the provisions of this Constitution, the person elected as the President shall have power to issue a proclamation for the holding of the first session of the National Assembly immediately after his being sworn in, or for its dissolution as provided in this section. C - Qualifications for Membership of National Assembly and Right of Attendance
This is the 1999 Constitution as published in 2004. Later amendments aren't included yet, so a section may have changed since.
Original source
Official Gazette · CFRN 1999 official PDF · printed page 47. Original document
Release: draft-c8d50d87fae9. Source scope, review and corrections