Legal provisions for optional referendums at national level

Constitution of the Kingdom of Bhutan

http://www.constitution.bt/TsaThrim%20Eng%20(A5).pdf

Article 34(2) The Druk Gyalpo (King) may command a National Referendum if

(a) in His opinion a Bill, which is not passed in a joint seating of parliament, is of national importance; or

(b) an appeal is made by not less than fifty percent of the total number of members of all Dzongkhag Tshogdues.