Legal provisions for optional referendums at national level

Referendums Act Chapter 2:10 (1999)http://?aceproject.?org/?regions-?en/?eisa/?ZW/?Referendums%20?Act%20?Chapter%20?2%20?10.?pdf

Article 3 

Whenever the President considers it desirable to ascertain the view of voters on any question or issue, he may by proclamation in the Gazette:(a) declare that a referendum is to be held in order to ascertain the view of voters on that question or issue