1987 Constitution of the Philippines
Section 23.
The Congress, by a vote of two-thirds of both Houses in joint session assembled, voting separately, shall have the sole power to declare the existence of a state of war.
In times of war or other national emergency, the Congress may, by law, authorize the President, for a limited period and subject to such restrictions as it may prescribe, to exercise powers necessary and proper to carry out a declared national policy. Unless sooner withdrawn by resolution of the Congress, such powers shall cease upon the next adjournment thereof.