Under this option, a number of willing EU Member States, probably on the basis of the present composition of the euro area, would decide to go ahead and develop more intense cooperation in some areas, using all existing legal possibilities to do that. This would neither make it necessary to modify the current EU treaties nor to conclude a new international legal instrument. It could be publicly announced by a Political Declaration of the heads of state or government of the willing EU Member States.

It would depend on the political will of those states to decide to which matters their enhanced cooperation would apply. Decisions would have to be adopted in accordance with the rules of the treaties and within the EU institutional framework; on this basis, they could be adopted and implemented by the participating Member States only. Some cooperation could also possibly be developed outside the EU institutional framework, on the condition of fully respecting the EU treaties and EU law, as well as the rights of the non-participating Member States.