Issues of sub-national referendums regulated at the national level

Hungary'sConstitution of 2011

https://www.constituteproject.org/constitution/Hungary_2011.pdf

Local governments

Article 31

1. In Hungary local governments shall be established to administerpublic affairs and exercise public power at a local level.

2. A local referendum may be held on any matter within theresponsibilities and competences of local governments as defined by law.

3. The rules of local governments shall be defined by a cardinal Act.

Act XXXVI of 2013on Electoral Procedure

http://valasztas.hu/en/ovi/241/241_1_10.html

Section 349

(1) The provisions of Act C of 1997 on Election Procedure shall beapplied:

[….]

c) in national and local referendums, national and local popularinitiatives and citizens’ initiatives until the entry into force of the Act onNational and Local Referendums, National and Local Popular Initiatives andCitizens’ Initiatives.

Act C of 1997 on Electoral Procedure