Legal provisions for mandatory referendums at national level

Constitution (1996)

http://www.infoukes.com/history/constitution/index-en.html

Article 73.

Issues of altering the territory of Ukraine are resolved exclusively by an All-Ukrainian referendum.

Article156.

“A draft law on making amendments to Title I General Principles, Title III Elections, Referendum, and Title XIII Making Amendments to the Constitution of Ukraine, shall be submitted to the Verkhovna Rada of Ukraine by the President of Ukraine, or by not less than two-thirds of the constitutional membership of the Verkhovna Rada of Ukraine, provided that it is adopted by at least two-thirds of the constitutional members of the Verkhovna Rada of Ukraine, be approved by an All-Ukrainian referendum called by the President of Ukraine.