Staying in the EUCU requires consent of the Council of Europe—Parliament can put in primary legislation that they wish to remain in the EUCU, but they have no p

Staying in the EUCU requires consent of the Council of Europe—Parliament can put in primary legislation that they wish to remain in the EUCU, but they have no power to enact it. You cannot make Article 50 conditional, as once the notification is sent you cannot unsend it—you are stuck with whatever is agreed between the state and the Council of Europe (or nothing, if no agreement is made within two years, or longer with unanimous agreement).