Dear Members of Parliamentarians for Global Action (PGA);
Dear Parliamentarians supporting the ICC and the fight against impunity;
On Saturday 12 June 2010, at 0.20 AM, the Kampala Review Conference, without a vote, and after two weeks of intense negotiations, approved the amendment to the Rome Statute of the ICC concerning the crime of aggression [see http://www.icc-cpi.int/iccdocs/asp_docs/Resolutions/RC-Res.4-ENG.pdf ]
as well as the conditions for the exercise of the ICC jurisdiction over this crime.
While reaching international consensus on the definition of aggression in the realm of international criminal justice and for the purpose of applying the principle of individual criminal responsibility is an historic achievement for the international community, the jurisdictional regime of the ICC on aggression would appear to be seriously weakened by a full exemption for Nationals from Non Parties to the Rome Statute and through a "delayed entry into force" of the amendment, which may take place only after the following conditions are met: (A) a decision of at least 2/3 of the current 111 ICC Member States is taken in favor in 2017 and (B) at least 30 States will have ratified the amendment. 
The five Permanent Members of the UN Security Council have exercised their influence on this jurisdictional regime, adhering strongly to their position that the determination of an act of aggression by a State against another State should be considered as an exclusive prerogative of the Security Council under Chapter VII of the UN Charter.  Other States from Latin America, the Caribbean, Africa and Europe affirmed that the Council has a primary, but not exclusive, responsibility in this domain.
A diplomatic compromise was struck by Review Conference chair Ambassador Christian Wenaweser through allowing for a delayed entry into force.  The unprecedented exemption of Non-Parties Nationals from the Court's jurisdiction in case of proprio motu prosecutions and referrals of situations by States Parties was agreed upon by ICC States Parties with certain Non-Parties.
The PGA Campaign for the Effectiveness and Universality of the Rome Statute system will now have to carefully analyse the outcome of Kampala and make choices regarding next steps of the Campaign vis-a-vis this important package of amendments to the Rome Statute on the crime of aggression.
An initial assessment of our PGA ICC team is that criminalising aggression is highly symbolic and sends a powerful signal to would-be aggressors, even if --after 2017-- the jurisdictional regime of the Court may not be as strong and effective as the one that the Court has for the other core crimes under international law, namely genocide, crimes against humanity and war crimes. 
In this respect, while in 2017 there might be a vote, the only option that seemed available in Kampala has been general agreement (consensus or unanimity), given the absence of a significant number of States who were not present at the first Review Conference of the Rome Statute.
In evaluating the Kampala Review Conference, PGA Members will also have to take into account the inclusion in the Statute of certain prohibited weapons (e.g. gas) in internal armed conflicts,  a positive development that seeks to align the incriminated conduct in international and civil wars, as well as, unfortunately, the missed opportunity to delete from the Statute the transitional provision that gives the opportunity to States to exempt their nationals and territories from the ICC jurisdiction on war crimes for the first 7 years after ratification : This negative development is however mitigated by the decision to again review this provision (article 124) at the 2015 Assembly of States Parties to the Rome Statute.