The package proposed by the President of the European Council (“the Tusk Package” or “the Package”) consists of (i) a Draft Decision of the Heads of State or Government meeting within the European Council (“the MS Decision”), (ii) a Draft Decision of the Council (“the Council Decision”) and (iii) four Declarations (“the Declarations”), one from the European Council (“the EC Declarations”) and three from the Commission (“the Commission Declarations”). The objectives and contents of the package are clarified in Tusk’s accompanying letter.
The MS Decision is not an act of the European Council (EC). It is an act the Member States (MS) adopted within the EC but outside the EU legal framework. Additionally, it is not a decision; it is, in substance, an international agreement between MS, which is formally termed a decision.
Under Section E, the MS Decision would take effect on the same day that the UK informs the Council of its decision to remain a member of the EU. Thus, the Decision is meant to be binding and subject only to the outcome of the UK referendum.
Since the Decision is not subject to ratification by Member States, it is to be construed as an international agreement concluded in a simplified form, i.e., entering directly into force upon signing by the Heads of State or Government of the MS.