In December 2017, the International Criminal Court (ICC) Assembly of States Parties considered how and when to activate the Court’s jurisdiction over the crime of aggression. It confirmed that the Court does not have jurisdiction in respect of the territory or nationals of a State that has not ratified the crime of aggression amendments to the Rome Statute, absent a UN Security Council resolution. This position is entirely consistent with Article 121(5) and all other Articles of the Rome Statute. It is now for each State to choose whether to ratify the relevant amendments, and thereby accept the Court’s jurisdiction. To date, only 35 States Parties have done so. The UK has no plans to ratify the amendments, as we consider that the UN Security Council has the primary responsibility for the maintenance of international peace and security, and it is for the UN Security Council to determine when an act of aggression has occurred, as provided for in the UN Charter.