Yes I don't see any reason why you cant you the same rules. Therefore following rules can used to determine whether two government departments are related or not. [IAS 24.9]:
(b) An entity is related to a reporting entity if any of the following conditions applies:
(i) The entity and the reporting entity are members of the same group (which means that each parent, subsidiary and fellow subsidiary is related to the others).
(ii) One entity is an associate or joint venture of the other entity (or an associate or joint venture of a member of a group of which the other entity is a member).
(iii) Both entities are joint ventures of the same third party.
(iv) One entity is a joint venture of a third entity and the other entity is an associate of the third entity.
(v) The entity is a post-employment defined benefit plan for the benefit of employees of either the reporting entity or an entity related to the reporting entity. If the reporting entity is itself such a plan, the sponsoring employers are also related to the reporting entity.
(vi) The entity is controlled or jointly controlled by a person identified in (a).
(vii) A person identified in (a)(i) has significant influence over the entity or is a member of the key management personnel of the entity (or of a parent of the entity).