Legal provisions for optional referendums at national level

Constitutionof the Islamic Republic of Pakistan

 (adopted in February 1956, last amended inFebruary 2010)

http://www.pakistani.org/pakistan/constitution/

Article48(6).

Ifat any time the Prime Minister considers it necessary to hold a referendum onany matter of national importance, he may refer the matter to a joint sittingof the Majlis-e-Shoora (Parliament) and if it is approved in a joint sitting,the Prime Minister may cause such matter in the form of a question that iscapable of being answered in the form by either 'Yes' or'No'.

EighteenthAmendment Act 2010

http://www.pakistani.org/pakistan/constitution/amendments/18amendment.html