One, however, must notforget the broader constitutional tensions underlying the EU’s and the ECJ’s relationshipwith international law. On the one hand, the ECJ emphasises that as such, it isnot against the EU’s accession to an agreement having its own dispute settlementmechanism1.On the other hand, the envisaged agreement and its dispute settlement bodycannot affect the constitutional framework and founding principles of the EU legalorder2.

Thecriteria of compatibility laid down by the ECJ have become more difficult to meetand can be grouped in several areas. One of the areas concernsthe safeguarding of EU fundamental rights. This area became a lot more relevantafter Kadi3,as exemplified by Opinion 2/13 and has two facets to it. First, every EU act, evenEU international agreements, must respect EU fundamental rights4.Furthermore, an assessment of the EU’s internal provisions on the division ofpowers would occur, if the extra- EU court had to decide on whether a specificact or omission is attributable to the EU or a Member State5.  Second area relates to the preliminary referenceprocedure. First, the ECJ will not find an incompatibility if an internationalagreement includes a preliminary reference procedure, provided that it is the ECJthat has to deliver the ruling (and not the extra EU court as seen in Opinion2/13) and that the ruling is binding on the extra-EU referring court. Third areaconcerns other fundamental principles or values of the EU.

According toOpinions 2/13 and 1/09, the ECJ will not accept a system that might affect theprinciples of direct effect, primacy or sincere cooperation.                                                   The following section willaddress the compatibility of the proposed ICS with the EU legal order in lightof the afore mentioned aspects. The overall tension between the EU’s role as aninternational actor and the ECJ’s role as the EU’s constitutional court willprovide the guiding thread throughout the next section about the ECJ’s exclusivejurisdiction to provide binding interpretations of EU law.1 Court of Justice, Opinion 1/91paras 40 -70; Opinion 1/09, para 74; Opinion 2/13 para 182.2 Court ofJustice, Opinion2/13  para 158.3 Kadi, supra note 176.4 Court of Justice, Opinion1/00  para 16.5 Court of Justice, Opinion2/13  paras 22 -24