Legal provisions for optional referendums at national level
Sudan
Answer
Yes
Source
The Interim National Constitution of the Republic of Sudan (from 2005) http://www.mpil.de/shared/data/pdf/inc_official_electronic_version.pdf
ReferendumArt. 217 (1) The President of the Republic or the National Assembly, by resolution passed by more than half of the members, may refer to referendum any matter of national or public interest.
