VIEW OF ADVOCATE GENERAL JÄÄSKINEN

delivered on 13 May 2014 ( 1 )

Opinion of the Court 1/13

Request for an opinion submitted by the European Commission

‛Request for an opinion pursuant to Article 218(11) TFEU — Admissibility — Concept of ‘agreement envisaged’ — International agreements in the field of judicial cooperation in civil matters — Hague Convention of 25 October 1980 on the Civil Aspects of International Child Abduction — Exclusive external competence or shared external competence of the European Union to accept the accession of a third State to the convention — Conclusion of an international agreement which may affect common rules of EU law or alter their scope, within the meaning of Article 3(2) TFEU — Area already covered to a large extent by rules of EU law — Risk of undermining the uniform and consistent application of the rules of EU law and the proper functioning of the system which they establish — Interplay with Regulation (EC) No 2201/2003’

Table of contents

I – Introduction II – The background to the request for an opinion III – Procedure IV – Admissibility A – The nature of the instruments which are the subject of the present request for an opinion B – The parties to the international agreements at issue C – The status of the international agreements in question V – The substance A – Introductory remarks B – The criteria for demarcating the exclusive external competence of the European Union deriving from the case-law prior to the FEU Treaty C – The continued relevance of the principles laid down in case-law after the entry into force of the FEU Treaty D – The application to the present case of the criteria relating to the effect on common rules 1. The characteristics of the international agreements at issue 2. The existence of common rules in the area covered by the international agreements in question 3. The risk that the common rules in question might be affected by the international agreements at issue VI – Conclusion

I – Introduction

1. This View is given in the context of a request for an opinion submitted to the Court by the European Commission pursuant to Article 218(11) TFEU. ( 2 ) The question put to the Court in this case is whether or not the acceptance of the accession of third States to the Hague Convention of 25 October 1980 on the Civil Aspects of International Child Abduction (‘the 1980 Hague Convention’) ( 3 ) falls within the exclusive competence of the European Union. That question is asked, in particular, in light of the changes which the Treaty of Lisbon has made to the division of competences between the European Union and its Member States, which the Court is now called upon to elucidate.

2. It is appropriate to clarify at the outset that it is the individual Member States themselves, rather than the European Union as such, that are parties to the 1980 Hague Convention, since the convention does not permit the accession of international organisations. Nevertheless, the Commission has taken the view that the option of accepting the accession to the convention of third States, as provided for in Article 38 of the convention, falls within the exclusive external competence of the European Union and that the Member States may not, therefore, accept such accessions individually and on their own behalf, but must do so simultaneously and in the interests of the EU. The proposals for Council decisions to that effect which have been presented by the Commission have been rejected by a large majority of the Member States, most of which have already accepted the accession to the convention of at least one third State.

3. In justification of its approach, which is contested both by the Council of the European Union and by almost all of the Member States that have submitted observations in the present case, ( 4 ) the Commission, supported by the European Parliament, argues that what is at issue here is the conclusion of an international agreement which may affect common rules of EU law or alter their scope, within the meaning of Article 3(2) TFEU.

4. Specifically, there would appear to be a risk of competition, or even conflict, with Council Regulation (EC) No 2201/2003 of 27 November 2003 concerning jurisdiction and the recognition and enforcement of judgments in matrimonial matters and the matters of parental responsibility, repealing Regulation (EC) No 1347/2000 ( 5 ) (‘the Brussels IIa Regulation’). Indeed, the scope ratione materiae of that regulation overlaps with that of the 1980 Hague Convention inasmuch as it too contains provisions on the cross-border abduction of children, some of which refer back to the convention. The question therefore arises of whether the criteria for determining whether there is a risk that common rules will be affected by an international agreement that were defined by the Court in its case-law prior to the entry into force of the FEU Treaty remain relevant in this case.

5. In any event, before determining whether the European Union has exclusive external competence or shared external competence to accept the accession of third States to the convention, the Court must consider whether the present request for an opinion is admissible, a matter regarding which there are serious doubts.

6. First of all, it is necessary to ascertain whether the instruments which are the subject of this request for an opinion are in fact ‘agreements’ covered by Article 218(11) TFEU. Indeed, the instruments in question are atypical, insofar as concerns both their nature and the contracting parties, inasmuch as they comprise a series of declarations of acceptance of the accession of third States to the convention made by the Member States rather than by the European Union itself. In the event that that question is answered in the affirmative, it will then be necessary, given the factual context outlined above, to determine whether the agreements at issue are still ‘envisaged’, within the meaning of Article 218(11) TFEU, and to what extent the Court may, accordingly, provide a useful opinion.

II – The background to the request for an opinion

7. The objects of the 1980 Hague Convention, which entered into force on 1 December 1983, are, according to Article 1 thereof, ‘to secure the prompt return of children wrongfully removed to or retained in any Contracting State’ and ‘to ensure that rights of custody and of access under the law of one Contracting State are effectively respected in the other Contracting States’.

8. Between 2007 and 2011, eight third States, namely the Republic of Armenia, the Republic of Albania, the Republic of the Seychelles, the Kingdom of Morocco, the Gabonese Republic, the Republic of Singapore, the Principality of Andorra and the Russian Federation, successively deposited instruments of accession to the said convention. ( 6 )

9. Every State that accedes to the 1980 Hague Convention is, in accordance with the first to third paragraphs of Article 38 thereof, ( 7 ) bound by the convention. However, it is clear from the fourth and fifth paragraphs of Article 38 that the accession of any new State is subject to an acceptance procedure, such that any accession will take effect only as regards relations between the acceding State and such contracting States as declare their acceptance of its accession. ( 8 )

10. Although the Member States alone are parties to the convention, and not the European Union, the Commission has nevertheless taken the view that the international abduction of children is a matter that falls within the exclusive external competence of the European Union as a result of the adoption of the Brussels IIa Regulation and the inclusion within that regulation of the content of the convention. Consequently, on 21 December 2011, it adopted eight proposals for Council decisions on the declarations of acceptance by the Member States, in the interests of the European Union, of the accession to the convention of each of the eight third States. ( 9 )

11. The European Parliament voted in favour of those proposed decisions. ( 10 ) Within the Council, on the other hand, the representatives of the majority of the Member States opposed them. They argued that the Council was under no legal obligation to adopt them, since the matter of declaring the acceptance of a third State’s accession to the 1980 Hague Convention did not, they maintained, fall within the exclusive external competence of the European Union, the convention being, first and foremost, an instrument of bilateral cooperation between the contracting States. ( 11 ) Consequently, the Council did not adopt the proposed decisions.

12. Moreover, the majority of the Member States had already individually declared their acceptance of one or more of the accessions in question and, in some cases, had done so long before the date of the abovementioned Commission proposals. ( 12 )

13. In the circumstances, the Commission regarded it as appropriate to request an opinion of the Court pursuant to Article 218(11) TFEU and lodged the present request on 21 June 2013, in which it asks the following question: ‘Does the exclusive competence of the [European] Union encompass the acceptance of the accession of a non-Union country to the [1980 Hague Convention]?’

III – Procedure

14. Written observations were lodged by the Commission, the European Parliament, the Council and the Czech, German, Estonian, Irish, Greek, Spanish, French, Italian, Cypriot, Latvian, Lithuanian, Austrian, Polish, Portuguese, Romanian, Slovak, Finnish, Swedish and United Kingdom Governments.

15. The Court posed a question for a written answer on the possible implications for the present case of the particular situation of the Kingdom of Denmark. ( 13 ) The Commission, the European Parliament, the Council and the Czech, Danish, Spanish, French and Polish Governments answered that question.

16. At the hearing on 1 April 2014, representatives of the Commission, the European Parliament, the Council and the Czech, Danish, German, Greek, Spanish, French, Italian, Latvian, Polish, Romanian, Finnish, Swedish and United Kingdom Governments made oral submissions.

IV – Admissibility

17. The Council and 11 of the Member States that have lodged written submissions ( 14 ) either entertain doubts as to the admissibility of this request for an opinion or categorically contest its admissibility, while the Commission and the European Parliament take the contrary view. For my part, I consider that the request ought to be ruled only partly admissible, for the reasons which I shall set out below.

18. It is clear from Article 218(11) TFEU that the Commission ( 15 ) may obtain the opinion of the Court of Justice on any question relating to the ‘[compatibility] with the Treaties’ of any ‘envisaged’‘[international ( 16 )] agreement’ and that ‘[w]here the opinion of the Court is adverse, the agreement envisaged may not enter into force unless it is amended or the Treaties are revised’.

19. According to the settled case-law of the Court of Justice, the tenor of which is reproduced in Article 196(2) of its Rules of Procedure, an opinion of the Court may address not only the question whether the conclusion of such an agreement is compatible with substantive rules of EU law, ( 17 ) but also, as in the present case, the question of whether or not an envisaged agreement falls within the European Union’s spheres of competence. ( 18 )

A – The nature of the instruments which are the subject of the present request for an opinion

20. The first question that arises in this case is whether Article 218(11) TFEU indeed applies to instruments such as those with which the present request for an opinion is concerned. ( 19 )

21. It must be observed at the outset that the issue in the present case is not the negotiation or conclusion, or even the revision of the 1980 Hague Convention as such. The sole issue in this case is the application of Article 38 of the convention and the exercise, by the States that are already parties to the convention, of the prerogative conferred on them by Article 38 to decide whether or not to enter into a binding relationship with newly acceding States. In other words, the question raised by the Commission concerns, in substance, the division of competences between the European Union and the Member States not in connection with any alteration of the scope ratione materiae of the 1980 Hague Convention, but solely in connection with the extension of the territorial scope of the convention.

22. In its objection to the admissibility of the present request for an opinion the German Government argues that, according to its literal meaning, an agreement necessarily requires the meeting of two corresponding expressions of intent. It maintains that the accession of a third State to the 1980 Hague Convention, on the one hand, and the acceptance of that accession on the part of a contracting State, on the other, do not satisfy that requirement, even if those two elements are considered as forming an inseparable whole, ( 20 ) since such acts do not have the characteristics of a reciprocal contractual relationship. ( 21 )

23. That, in my view, is a purely theoretical argument and must be rejected. Indeed, it is clear from the case-law of the Court of Justice that, from the outset, the Court has consistently opted for a broad, non-formalistic definition of the types of international agreement that may be the subject of a request for an opinion. ( 22 )

24. Furthermore, in accordance with Article 15(a) of the Vienna Convention on the law of treaties ( 23 ) (‘the Vienna Convention’), the consent of a State to be bound by a treaty may be validly expressed by accession, where the treaty so provides. That is the case under the 1980 Hague Convention.

25. It is true that Article 38 of the 1980 Hague Convention establishes a system for the exchange of declarations of intent which produces effects only as between the parties, since, in accordance with the terms of that provision, any accession to the convention will take effect only as regards relations between the acceding State and those of the contracting States which declare their acceptance of that accession. In that regard, this simplified system differs from the traditional procedures for accession to a multilateral convention. Nevertheless, it fulfils the requirements of the Vienna Convention, in particular those set out in Article 11 thereof. ( 24 )

26. The special nature of the 1980 Hague Convention thus resides in the fact that accession is not an act of a multilateral nature, but one which calls for the acceptance thereof by each individual State already party to the convention, and that the effects of any such acceptance are restricted to the relationship established between the two States in question. In practice, this simplified procedure for the conclusion of any new accession agreement gives rise to a series of bilateral relationships governed by international law, the content of which is identical to that of the 1980 Hague Convention. ( 25 ) The objective of such a mechanism is to allow the contracting parties the freedom to determine which States it will enter into a binding agreement with under the convention, that is to say, the same freedom of choice as existed when the convention was initially concluded.

27. However, this special mechanism, which is entirely consistent with the principle of freedom to contract that underlies the law of treaties, does not alter the fact that an act of accession and a declaration of acceptance of that accession together create a reciprocal contractual relationship between the two States in question, which may therefore be regarded as constituting, in and of itself, a genuine international ‘agreement’ for the purposes of Article 218(11) TFEU, without there being any need to consider whether such a declaration of acceptance is independent from or ancillary to the text of the 1980 Hague Convention itself.

28. Therefore, in light of both the object and the nature of the instruments which are the subject of this request for an opinion, the question raised in this case concerns a matter which may fall within the scope of Article 218(11) TFEU.

B – The parties to the international agreements at issue

29. Given the exchange of arguments in the present case, it is appropriate, secondly, to verify that the agreements in question, that is to say, the declarations by which the Member States accept the accession of third States to the 1980 Hague Convention, may indeed be regarded as falling within the scope of Article 218(11) TFEU even though the European Union is not, as such, a party to those agreements.

30. The wording of that provision is not explicit as regards the identities of the parties to the international agreements that may be the subject of an opinion of the Court. Unlike paragraph 1 of Article 218 TFEU, paragraph 11 does not specify whether or not such agreements must be ‘between the Union and third countries’. ( 26 )

31. On the other hand, it is clear from the case-law of the Court, and in particular from Opinion 2/91, that the fact that it is the Member States acting jointly in the European Union’s interests that are parties to the instrument in question, rather than the EU itself, has no bearing on the admissibility of a request for an opinion, since the EU is capable of exercising its external competence through the intermediary of the Member States. ( 27 ) That case-law appears to me to be highly relevant in the present case.

32. There is no question that it is impossible for the European Union as such to be a party to the 1980 Hague Convention, since the convention contains no clause authorising the accession of a regional economic integration organisation such as the European Union, ( 28 ) even though the European Union is now a member of the Hague Conference on Private International Law (‘the HCCH’). ( 29 )

33. Therefore, it is the Member States of the European Union, all of which are contracting parties to the convention, that alone have power formally to accept the accession of a new State, pursuant to the fourth paragraph of Article 38 of the convention. However, they could also accept an accession in the interests of the European Union, if the latter were to take the initiative and call on all the Member States and authorise them to take such action, such a mandate reflecting the EU’s intention to exercise its external competence through the intermediary of the Member States, since it is unable to take such action itself. ( 30 )

34. Accordingly, in its request for an opinion of the Court, the Commission argued that, in order to be able to accept the accession of a third State to the 1980 Hague Convention, the Member States would be required first to obtain an authorising decision of the Council, which is a legal requirement where an agreement falls within the exclusive competence of the European Union. Moreover, in each of the abovementioned proposals for a Council decision, ( 31 ) the Commission recommended that the Member States should act ‘in the interest of the European Union’ and ‘simultaneously ... within a time frame established by the Council Decision’ on the basis of ‘Article 218 [TFEU] together with Article 81(3)’. ( 32 )

35. In the event that the Court should consider that the European Union does indeed have exclusive competence in the field to which the envisaged agreements relate, that process of authorising the Member States would be necessary, since, according to the European Union’s own legal rules, those agreements would normally have to be concluded by the European Union alone. ( 33 )

36. I would emphasise in this connection that it is possible to identify three distinct situations in which the Member States may intervene in a matter in which the European Union has exclusive external competence, without that formally entailing any agreement ‘between the Union and third countries’ as referred to in Article 218(1) TFEU. ( 34 ) The first is where the Member States act jointly in the interests of the European Union. ( 35 ) The second is where a Member State concludes an international agreement individually, but in the interests of the European Union, ( 36 ) and the third is where a Member State acts on its own behalf but in a way that is compatible with the interests of the European Union. ( 37 )

37. Whenever the matter in question falls within the sphere of the European Union’s exclusive competence, it is necessary, in each of those three situations, for the EU to empower the Member States, in accordance with Article 2(1) TFEU. The necessary authorisation may take one of a number of different forms and may be subject to certain conditions. ( 38 ) It is clear from the case-law mentioned above ( 39 ) that the procedure for obtaining an opinion of the Court provided for by Article 218(11) TFEU is available at least in the first of the three situations outlined.

38. I would clarify that, where an international agreement is concluded in such a manner in the interests of the European Union and pursuant to an express authorisation from the Council, ( 40 ) it will produce no legal effects in so far as concerns relations between the European Union and the third States in question. ( 41 ) The Member States alone will have entered into a binding commitment under international law toward such third States, and not the European Union itself. ( 42 ) In such a situation, the European Union will offer no guarantees or make any other international commitment. ( 43 ) It also goes without saying that third States cannot be bound by the effects of any such Council decision.

39. It follows, in my view, that the case-law of the Court relating to the admissibility of a request for an opinion of the Court concerning the European Union’s intention to commit itself in any given international agreement, and the time when its consent in that regard becomes final, is not applicable to the situation in the present case. ( 44 ) The Court’s opinion in the present procedure will affect solely the rights and obligations under EU law of the institutions on the one hand and the Member States on the other and will be confined to the question whether competence to act lies with the European Union or with the Member States.

40. Notwithstanding that particular context, in accordance with the rule expressed in Opinion 2/91, ( 45 ) it is perfectly acceptable for an opinion of the Court to address, as in the present case, the issue of the division of competences with regard to a draft international agreement to which the European Union would not formally be a party and which would be concluded through the intermediary of the Member States after they had been authorised to act jointly and in the interests of the European Union. ( 46 )

41. However, a third criterion, one of a temporal nature, by which the admissibility of the present request for an opinion must be assessed, will, I believe, have an effect on the request’s admissibility.

C – The status of the international agreements in question

42. It is important to emphasise that, in accordance with the wording of Article 218(11) TFEU, ( 47 ) which twice states that the agreement must be ‘envisaged’ ( 48 ) rather than finalised, a referral to the Court for the purpose of obtaining its opinion must be made ex ante, that is to say, before the agreement in question is concluded.

43. Indeed, as the Court pointed out in the very first opinion it gave, the purpose of the procedure is ‘to forestall complications which would result from legal disputes concerning the compatibility with the Treaty of international agreements binding upon the Community [now the European Union]’. ( 49 )

44. The procedure is therefore designed, primarily, to prevent the liability of the European Union being put in issue in the event that the legality of the international agreement in question is disputed after it has been concluded, ( 50 ) since that would give rise to adverse consequences for all interested parties, including third States. ( 51 ) Similarly, in a case such as the present, where the European Union itself has no capacity to conclude an agreement, ( 52 ) an opinion of the Court can help to avoid the legal ‘complications’ which could arise if Member States entered into commitments under agreements without the necessary authorisation where, under EU law, they no longer have the necessary legislative competence to put those commitments into effect.

45. Obviously, that preventive function is no longer relevant and a request for an opinion will no longer serve any purpose where the international agreement to which it relates is no longer in draft form but, on the contrary, has already become binding on the contracting States. ( 53 ) It is in the light of that functional interpretation of the concept of ‘agreement envisaged’ that one must reason in this case.

46. It is not in dispute that, in this case, the majority of the Member States have, individually and on their own behalf, already accepted the accession of one or more or even all eight of the third States that have acceded to the 1980 Hague Convention and are referred to in the request for an opinion. More specifically, on the date on which the request for an opinion of the Court was submitted, 21 June 2013, of all the 28 Member States, the only States not to have accepted any of the accessions in question were the Republic of Austria, the Portuguese Republic, the United Kingdom of Great Britain and Northern Ireland and the Kingdom of Denmark, albeit that that last State has a special status within the European Union as regards judicial cooperation in civil matters. ( 54 ) As regards the remaining 24 Member States, at least one of the agreements with the third States referred to in the request for an opinion has already been concluded as a result of their acceptance of the latter’s accession to the convention.

47. As regards the declarations of acceptance thus deposited by those Member States, it must be recognised that none of them may be regarded as constituting an international agreement that was still ‘envisaged’ at the time when the request to the Court was made, even though that requirement is expressly laid down in Article 218(11) TFEU. That in itself precludes the Court from delivering an opinion on that basis. In accordance with the case-law of the Court referred to above, I consider that the present procedure has lost both its purpose and its effectiveness in so far as it relates to the series of declarations of acceptance of accession which have already taken effect under international law, and that, consequently, the request is inadmissible in so far as they are concerned.

48. On the other hand, the request for an opinion is, I believe, admissible in so far as it relates to the European Union’s competence to express its position on the declarations of acceptance which, on the date when the request was submitted, had not yet been deposited by the Member States other than the Kingdom of Denmark, ( 55 ) since the bilateral agreements in question were still at that time only in draft form, and thus merely ‘envisaged’ within the meaning of Article 218(11) TFEU.

49. As the representative of the Commission acknowledged at the hearing, whatever position the Court adopts with regard to the substance of the case, the present procedure will not lead to any alteration of the situation under international law, in the sense that the commitments created by the acceptances of accessions already deposited will in no way be called into question by the Court’s response to the request for an opinion. At most, the present procedure might make it possible to establish whether the 24 Member States mentioned above have failed in some way to fulfil their obligations under EU law.

50. Like the Czech, Greek, French, Polish and Finnish Governments and the Council, I consider that a request for an opinion as provided for by Article 218(11) TFEU is not the appropriate legal remedy if the Commission’s objective in bringing the matter before the Court was in fact to put an end to the practice of a number of Member States of individually accepting the accessions of third States to the 1980 Hague Convention, as does appear to have been its intention. ( 56 ) As guardian of the Treaties, the Commission could, for that purpose, have initiated Treaty infringement proceedings pursuant to Article 258 TFEU ( 57 ) against the Member States that have adopted that practice, in so far as it amounts to an encroachment upon the realm of competences reserved to the European Union, ( 58 ) as it did in the cases which led to the ‘open skies’ judgments, ( 59 ) albeit that that type of procedure entails the observance of principles that do not apply in the procedure for obtaining an opinion of the Court. ( 60 )

51. In view of all the foregoing considerations, I propose that the Court should declare the present request for an opinion admissible only in part, that is to say, solely to the extent that it relates to those of the declarations of acceptance of the accession to the 1980 Hague Convention of the third States in question which, when the request was submitted, had not yet been deposited by the Member States, ( 61 ) leaving aside the particular case of the Kingdom of Denmark. As to the remainder, that is to say, the declarations of acceptance that had already been deposited by that date, the request for an opinion should, in my view, be declared inadmissible on the ground that it relates not to any ‘agreement envisaged’ within the meaning of Article 218(11) TFEU, but to agreements that have already been concluded.

V – The substance

A – Introductory remarks

52. It should be borne in mind, as a preliminary point, that the purpose of the procedure for obtaining an opinion of the Court provided for by Article 218(11) TFEU is, in addition to the avoidance of conflicts of laws, ( 62 ) to define the scope, under the rules of EU law alone, of the respective competences of the European Union and its Member States in the area concerned by the international agreement at issue, not to determine whether the European Union has capacity, under Articles 216 TFEU and 217 TFEU, ( 63 )to enter into and be bound by such an agreement. ( 64 )

53. Furthermore, it is common ground that, ‘[s]ince the entry into force of the Treaty of Amsterdam, [under Title IV of the EC Treaty] the Community [now the European Union] has competence to adopt measures in the field of judicial cooperation in civil matters having cross-border implications insofar as necessary for the proper functioning of the internal market. The Community [and subsequently the European Union] has exerted this competence by adopting a number of instruments, many of which coincide, partially or fully, with the areas of work of the HCCH.’ ( 65 )

54. There is an overlapping of this kind, in particular, between the provisions of the 1980 Hague Convention and those of the Brussels IIa Regulation in the sensitive area of the international abduction of children. The question referred in the present request for an opinion, namely whether the European Union has exclusive competence to accept the accession of third States to that convention, is therefore particularly pertinent.

55. All of the institutions and the vast majority of the governments that have submitted observations ( 66 ) are agreed that the European Union does indeed have competence to conclude an international agreement of this type. I too am of the opinion that the principle of such external competence must be taken for granted in the present case, bearing in mind that such authority may either arise from an express conferral by the Treaties or may flow implicitly from other provisions of the Treaties or acts of secondary legislation of the European Union, where the prior adoption of common rules necessarily leads to that result, ( 67 ) as it does in the present case. Indeed, in the field of judicial cooperation in civil matters, Article 81 TFEU, and in particular paragraph 3 thereof, which concerns family matters, makes no express provision for the European Union’s competence to conclude international agreements in that field, but that competence flows indirectly from other provisions of EU law. ( 68 )

56. The institutions and governments just mentioned are very much more divided on the question of the nature of this external competence, that is to say, whether the European Union may exercise it exclusively or whether, on the contrary, the Member States retain some concurrent competence in the field. ( 69 ) While the Italian Government, the Commission and the European Parliament consider that the conditions for establishing exclusive competence on the European Union’s part are satisfied in the present context, the Council and the other governments that have expressed their position on the substance of the case contend, on the contrary, that the competence is shared. ( 70 ) For my part, I would opt for the former view, for reasons which I will set out below.

57. I would, however, observe that, should the Court find that the European Union does indeed have exclusive external competence, that would not call into question the Council’s discretion as to whether or not to make use of that competence in order to conclude the international agreements in question, through the intermediary of the Member States, which are parties to the 1980 Hague Convention, since it is accepted that the European Union has no power to do so itself. ( 71 ) Moreover, the decision that is to be given will not prejudge the question whether the Member States, thus authorised by the European Union to accept the accession of the third States in question, would find themselves under an obligation to do so, or whether, in the event that the European Union decided to refuse such an accession, they would be precluded from doing so. Indeed, those questions cannot be resolved in the context of a procedure for obtaining the opinion of the Court.

B – The criteria for demarcating the exclusive external competence of the European Union deriving from the case-law prior to the FEU Treaty

58. Before the entry into force of the Lisbon Treaty, the principles to be applied in determining whether the Community’s competence to conclude agreements of international scope was exclusive or not were defined by the Court, in particular, in its judgment in Commission v Council, the so-called ‘ERTA judgment’, ( 72 ) as was clearly stated in Decision 2006/719, mentioned above. ( 73 ) According to that decision, ‘[e]ven if there is no explicit reference to external competence in the EC Treaty, it results from the jurisprudence of the [Court] that the provisions of the EC Treaty referred to above constitute legal bases not only for internal acts of the Community, but also for the conclusion of international agreements by the Community. [ ( 74 )] The Community may conclude international agreements whenever the internal competence has already been used in order to adopt measures for implementing common policies, as listed above, or if international agreement is necessary to obtain one of the European Community’s objectives. [ ( 75 )] The Community’s external competence is exclusive to the extent to which an international agreement affects internal Community rules or alters their scope. [ ( 76 )] Where this is the case, it is not for the Member States but for the Community to enter into external undertakings with third States or International Organisations. An international agreement can fall entirely or only to some extent within exclusive Community competence.’

59. In other words, in accordance with the case-law just mentioned, exclusive external competence could be conferred on the Community implicitly where there was a risk that the envisaged international agreement might have an adverse effect on common rules derived from the Community’s earlier exercise of its internal competence, a principle which reveals a symmetry between the two types of competence. ( 77 )

60. The criterion of the effect on common rules was defined in the subsequent case-law of the Court. It evolved over the course of three principal stages, ( 78 ) the last of which is represented by Opinion 1/03. ( 79 ) In that opinion, the Court first of all stated that the three situations ( 80 ) outlined in Opinion 1/94 and referred to in the ‘open skies’ judgments mentioned above, were ‘only examples, formulated in the light of the particular contexts with which the Court was concerned’. ( 81 ) It then went on to state that, ‘[r]uling in much more general terms, the Court has found there to be exclusive Community competence in particular where the conclusion of an agreement by the Member States is incompatible with the unity of the common market and the uniform application of Community law, [ ( 82 )] or where, given the nature of the existing Community provisions ..., any agreement in that area would necessarily affect the Community rules within the meaning of the ERTA judgment’. ( 83 ) The Court has also stated that, in order for exclusive competence to be acquired on that last basis, ‘it is not necessary for the areas covered by the international agreement and the Community legislation to coincide fully’, ( 84 ) or for there to be any contradiction between the commitments resulting from the international agreement and the common rules. ( 85 )

61. As Advocate General Bot observed, ( 86 ) in Opinion 1/03 ‘the Court, having reviewed the case-law, appears to have reverted to a broader conception of the way common rules may be affected’ and ‘has also set out the analytical method for determining whether the criterion expressed by the words ‘an area which is already covered to a large extent by Community rules’ [ ( 87 )] is satisfied’. The Court has stated, in this connection, that the analysis must ‘be based not only on the scope of the rules in question but also on their nature and content’ and must ‘take into account not only the current state of Community law in the area in question but also its future development, in so far as that is foreseeable at the time of that analysis’. ( 88 ) It has also pointed out that ‘it is essential to ensure a uniform and consistent application of the Community rules and the proper functioning of the system which they establish in order to preserve the full effectiveness of Community law’. ( 89 )

62. I would add that the Court observed in that same opinion that ‘the Community enjoys only conferred powers and that, accordingly, any competence, especially where it is exclusive and not expressly conferred by the Treaty, must have its basis in conclusions drawn from a specific analysis of the relationship between the agreement envisaged and the Community law in force and from which it is clear that the conclusion of such an agreement is capable of affecting the Community rules’. ( 90 )

63. For the reasons which I shall set out below, I consider that both the criteria for delimiting the exclusive external competence of the European Union and the methods by which those criteria are to be applied, thus defined by the Court, remain relevant for the purposes of answering the question submitted here, even though the provisions of the FEU Treaty, rather than those of the EC Treaty, apply in this case.

C – The continued relevance of the principles laid down in case-law after the entry into force of the FEU Treaty

64. At present, under Article 3(2) TFEU, in addition to the exclusive competence conferred on it in the areas exhaustively listed in paragraph 1 of that article, ( 91 )‘[t]he Union ... also [has] exclusive competence for the conclusion of an international agreement when its conclusion is provided for in a legislative act of the Union or is necessary to enable the Union to exercise its internal competence, or in so far as its conclusion may affect common rules or alter their scope’ (my emphasis).

65. First of all, it must be noted that, given the general terms in which it is worded, that provision renders the exclusivity of the competence dependent solely on the substance of the agreement, without drawing any distinction by reference to the contracting parties. ( 92 ) Accordingly, it is irrelevant whether the agreement with a third State is concluded by the European Union itself or through the intermediary of its Member States, as is envisaged in the present case.

66. All of the parties that have submitted observations to the Court in the present case are agreed, and rightly so in my mind, that the decision as to whether the competence of the European Union is exclusive or not must be made in light of Article 3(2) TFEU and that only the last of the three situations contemplated by that provision is relevant in this case. Indeed, it is common ground that the conclusion of the international agreements at issue neither falls within the scope of an exclusive competence expressly provided for in a legislative act of the European Union nor is necessary to enable the European Union to exercise its internal competence in the area covered by the agreements. Therefore, the nature of the European Union’s external competence depends solely on the question whether the acceptance of the accession of third States to the 1980 Hague Convention entails a risk of affecting common rules or altering their scope, within the meaning of Article 3(2) TFEU.

67. The parties take divergent approaches to how the last element of that provision is to be interpreted, in particular when the area to which the envisaged international agreement relates is covered, at least in part, by relevant common rules, as appears to be the case in the present matter. According to the Commission, the European Parliament and the Italian Government, exclusive external competence might arise as a result of the fact that the area covered by the 1980 Hague Convention coincides to a large degree with rules of EU law, inasmuch as the convention contains provisions that are equivalent to and closely connected with those of the Brussels IIa Regulation and that regulation established a common uniform system based on the mechanism introduced by the convention. The Council, on the other hand, along with all the other governments that have participated in these proceedings, dispute that view and favour a stricter approach according to which, since the entry into force of Article 3(2) TFEU, the European Union cannot have exclusive competence in such circumstances.

68. In order to settle that issue, the principal question that must be resolved is whether the criteria defined in earlier case-law for determining whether internal rules are affected remain relevant, or even decisive, notwithstanding the changes introduced by the Lisbon Treaty. That question of continued relevance arises, in particular, with regard to the criterion, referred to in Opinion 2/91, ( 93 ) concerning whether or not the area in question is ‘already covered to a large extent by [EU] rules’ and the additional criterion, referred to in Opinion 1/03, ( 94 ) relating to the risk of undermining the ‘uniform and consistent application of the ... rules [of EU law] and the proper functioning of the system which they establish’.

69. Like Advocate General Kokott ( 95 ) and Advocate General Sharpston, ( 96 ) I consider that the criteria developed in case-law relating to the European Union’s exclusive external competence must remain valid in the new regulatory context of Article 3(2) TFEU, since it is apparent that that provision constitutes a codification of those criteria. ( 97 ) Even though the abovementioned forms of words were admittedly not reproduced verbatim in Article 3(2) TFEU in order to explain the concept of rules being affected, within the meaning of that paragraph, ( 98 ) it seems to me perfectly obvious that the case-law in question was taken into account by the authors of the FEU Treaty and that the criteria developed by the Court still apply, given the historic and regulatory context of the provision in question.

70. Indeed, an analysis of the history of the FEU Treaty reveals that those responsible for its drafting intended to preserve the applicability of the case-law on the matter, not to depart from it, as the Council contends, without, however, offering any evidence in support of its contention. ( 99 ) Bearing in mind that the FEU Treaty was largely inspired by the abortive project to conclude a Treaty establishing a Constitution for Europe, it is interesting to note that the members of the Convention on the Future of Europe were enjoined to draft the provisions of the proposed treaty ‘in accordance with existing jurisprudence of the Court of Justice’ and in such a way as to ‘make explicit the jurisprudence of the Court’. ( 100 )

71. Moreover, the broad approach which I favour is not contradicted by an examination of the system of which Article 3(2) TFEU forms part. In their arguments against the continued application of the criterion developed in case-law according to which it is sufficient, in order for the European Union to have exclusive competence, that the area is ‘already covered to a large extent by common rules’, the German, Estonian, Latvian, Austrian, Swedish and United Kingdom Governments refer to Protocol No 25 on the exercise of shared competence annexed to the EU and FEU Treaties, ( 101 ) and to the rule of pre-emption that governs shared competence, which is set out in Article 2(2) TFEU. They object that it is clear from the wording thereof that the consideration that must be given to the fact that the European Union has already exercised its internal competence can relate only to the specific matters governed by the EU act adopted, and not to the whole of the area in question. However, like the Commission, I am of the opinion that neither Protocol No 25 nor Article 2(2) TFEU, which is the sole provision to which that protocol refers, ( 102 ) creates any formal obstacle to the application of the case-law that pre-dates the FEU Treaty, since those provisions merely address the conditions for the exercise of shared competence and are in no way intended to restrict the scope of the exclusive competence provided for in Article 3(2) TFEU, as has already been demonstrated by other Advocates General. ( 103 )

72. On this point, Advocate General Kokott has emphasised very strongly that ‘exclusive competence under the third variant of Article 3(2) TFEU is not linked primarily to the mere existence or non-existence of common rules on a certain subject, but to the risk of those common rules being affected or their scope being altered. Such a risk can arise where an international agreement contains provisions whose substance is closely connected with [common] rules which already to a large extent govern the subject in question in EU law. Such [common] rules can be adversely affected by an international agreement even if the [common] rules and the international agreement do not regulate precisely the same “elements” (within the meaning of the Protocol No 25). Accordingly, the criterion, which has been developed in case-law, of an area which is already covered to a large extent by [common] rules has not lost any of its importance, following the entry into force of the Treaty of Lisbon’ ( 104 ) (my emphasis).

73. Therefore, I consider that the analytical framework thus developed by the Court in order to interpret the provisions of the EC Treaty which applied previously still fits the current provisions of Article 3(2) TFEU.

D – The application to the present case of the criteria relating to the effect on common rules

74. In order to determine whether the European Union has exclusive competence to conclude the international agreements which are the subject of the present request for an opinion of the Court, it is necessary to interpret and apply the provisions of Article 3(2) TFEU in the light of the case-law principles mentioned above. ( 105 ) Accordingly, the Court must examine, first, whether there are common rules in the area covered by those agreements and, secondly, the degree of risk of the content and/or scope of those rules being affected by the conclusion of the agreements. In the present case, it is necessary, in this connection, to make one or two preliminary remarks regarding the international agreements envisaged.

1. The characteristics of the international agreements at issue

75. In view of the observations which have been submitted to the Court, the question arises of whether the risk of the international agreements at issue affecting rules of EU law, within the meaning of Article 3(2) TFEU, must be assessed by reference to the 1980 Hague Convention or by reference to the declarations of acceptance of the accession of third States to that convention, or by reference to those two instruments taken together.

76. The Court’s reasoning in this case cannot, in my opinion, be based solely on the 1980 Hague Convention, since what is called for in the present procedure is an opinion regarding international agreements which do not alter the content of that convention but extend its geographic scope as between Member States of the European Union and third States. Conversely, the declarations of acceptance of the accession of new States which are in issue in this case cannot be regarded as having any independent existence, since the precise purpose of those acts is to bring about the operation of a provision of the convention, namely Article 38 thereof. ( 106 ) Clearly, it is necessary to recognise that those acts of accession are ancillary to the convention and that any assessment of the effects they produce would be meaningless if it failed to take account of the instrument which gives them their raison d’être and by virtue of which they produce their substantive effects.

77. The close connection between those two types of instrument necessarily has repercussions for the Court’s determination of whether the European Union’s competence is exclusive or shared and consequently they must be assessed together. In other words, account must be taken of the potential adverse effect on EU rules of both the provisions of the 1980 Hague Convention and those of the declarations of acceptance which may interfere with those rules.

78. On the other hand, the fact that only certain elements of the international agreements envisaged compete or conflict with rules of EU law is irrelevant to that assessment. Indeed, as Advocate General Sharpston has pointed out, ‘[t]he use [in Article 3(2) TFEU] of the words “in so far as” makes it clear that parts of an international agreement can fall within the exclusive competence of the European Union on this basis whereas competence might still be shared with respect to other parts’. ( 107 ) That approach is supported both by recent legislation ( 108 ) and by the case-law of the Court preceding the FEU Treaty, from which it is clear that the European Union may acquire exclusive competence even where the areas covered respectively by the common rules and by the international agreement in question do not fully coincide ( 109 ) and that it is in fact necessary to compare the common rules in question with the essential purpose of the international agreement at issue. ( 110 )

2. The existence of common rules in the area covered by the international agreements in question

79. In accordance with the case-law criteria mentioned above, ( 111 ) in order to determine whether the international agreements envisaged concern ‘an area which is already covered to a large extent by [common] rules’, it is necessary to refer both to the scope of the relevant common rules and to their nature and content, account being taken not only of their current state but also of their future development, where this is foreseeable.

80. In the present case, it is undeniable that the matter of the civil aspects of the international abduction of children, which is precisely the subject of the 1980 Hague Convention and of the declarations of acceptance of the accessions to that convention, has already given rise to the exercise by the European Union of its internal competence, notably with the adoption of the Brussels IIa Regulation.

81. As regards the extent of those common rules, it is apparent that the scope ratione materiae of the said regulation is broader than that of the 1980 Hague Convention. The purpose of the latter is, by means of cooperation between the States that are parties to it, to ‘protect children internationally from the harmful effects of their wrongful removal or retention and to establish procedures to ensure their prompt return to the State of their habitual residence, as well as to secure [effective] protection for rights of [custody and] access’. ( 112 ) On the other hand, the Brussels IIa Regulation governs, as between the Member States of the European Union, ‘jurisdiction and the recognition and enforcement of judgments in matrimonial matters and the matters of parental responsibility’. ( 113 ) However, in so far as concerns the treatment, under civil law, of the cross-border abduction of children, the objectives of the regulation are identical to those of the convention and, as a result of the incorporation of the convention into the regulation, the latter contains a series of provisions which, although not completely identical, are equivalent. ( 114 )

82. It is appropriate to mention in this connection some of the main provisions of the 1980 Hague Convention, which include the following: Article 3, which defines the conditions under which ‘[t]he removal or the retention of a child is to be considered wrongful’, Articles 6 and 7, which concern the ‘central authorities’ that the contracting States must designate for the purposes of cooperation, ( 115 ) Articles 8 to 20, which address the ‘return of children’ and lay down the procedures which the central, judicial and administrative authorities of the contracting States must follow in order to secure the prompt return of children, except in exceptional circumstances, Article 16, which provides, in particular, that the judicial authorities of the State to which the child has been removed or in which it has been retained must not rule on the merits of rights of custody until it has been determined that the child is not to be returned under the convention, and Article 21, which provides that ‘[a]n application to make arrangements for organising or securing the effective exercise of rights of access may be presented to the Central Authorities of the Contracting States in the same way as an application for the return of a child’.

83. In addition to a similar definition of the concept of ‘wrongful removal or retention’ of a child, ( 116 ) the Brussels IIa Regulation contains a number of provisions which pursue the same objectives and thus cover the same subjects as the 1980 Hague Convention. Specifically, they are Article 10, which lays down a rule of special jurisdiction for the courts of the Member States ‘in cases of child abduction’, ( 117 ) Article 11, which details the procedures to be followed in order to obtain the ‘return of the child’, Articles 41 and 42, which, in the context of the recognition and enforcement of judgments given in a Member State, relate to the ‘[e]nforceability of certain judgments concerning rights of access and of certain judgments which require the return of the child’, and Article 53, which governs ‘cooperation between central authorities in matters of parental responsibility’.

84. Despite those similarities, it is clear from the preamble to the Brussels IIa Regulation ( 118 ) that the regulation is not intended to replace the 1980 Hague Convention entirely, but rather to supplement it. Chapter V of the regulation ( 119 ) governs the relationship between the two instruments and provides that the regulation is to take precedence over the convention in relations between the Member States, except in so far as concerns matters covered by the convention which are not governed by the regulation.

85. There is a significant overlap between these two instruments and the interplay between them is somewhat complex, as is evidenced by the provisions of Article 11 of the regulation, which seeks to reconcile two distinct objectives, namely continuity and change. That is the result of a political compromise between, on the one hand, those of the Member States that considered it unnecessary to have EU regulation in this field and, on the other, those that argued that the system established by the 1980 Hague Convention needed to be reinforced, in particular in order to counter the abusive use that had been made of the exception to the principle of prompt return laid down in Article 13(b) of the convention. ( 120 )

86. It is true that the territorial scope of the Brussels IIa Regulation differs from that of the 1980 Hague Convention in that it is limited to relations between the authorities of the Member States of the European Union. The rules relating to ‘decisions on parental responsibility, including measures for the protection of the child’ ( 121 ) laid down by the regulation are therefore not intended to apply where a process of cooperation between a Member State and a third State is necessary to bring about the return of an abducted child. Nevertheless, the regulation can apply where a child has its habitual residence in a third State ( 122 ) and the authorities of a third State thus become involved in that capacity. Furthermore, it cannot be ruled out that the acceptance or otherwise of the accession of a third State to the convention, which has given rise to the question in the present case, could have an effect even on relations between Member States, and I shall come back to that point. ( 123 )

87. As regards the nature of the common rules arising from the regulation, in particular in the area in which the regulation interacts with the 1980 Hague Convention, namely the cross-border abduction of children, it must be noted that the rules relating to the jurisdiction of the courts of the Member States and to the mutual recognition and enforcement of decisions given by those courts, are binding measures which bring about complete, rather than minimum harmonisation. In particular, Articles 11(3) and 15(5) of the Brussels IIa Regulation impose a duty on the competent authorities to act expeditiously, in particular, requiring compliance with a six-week deadline, uniformly and in more stringent terms than those used in Article 11 of the convention, which are purely indicative. The legislative powers of the Member States in these matters are therefore now greatly diminished.

88. Lastly, as regards the content of the common rules in question, it may be observed that some of the provisions of the Brussels IIa Regulation contain an express reference to the 1980 Hague Convention. ( 124 ) In addition to the mentions made in recitals 17 and 18 of the preamble to the regulation, references to the convention, and to Articles 12 and 13 thereof in particular, are made in Article 11(1), (2), (4), (6) ( 125 ) and (8) of the regulation, and indeed Articles 12 and 13 of the convention and the provisions of the regulation just mentioned address the same subject, namely the procedures for the ‘return of the child’. Article 42(2) of the regulation also refers to the effect that Article 13 of the 1980 Hague Convention may have on the enforceability of a decision of a Member State court requiring the return of a child. It follows that the conditions laid down in the aforementioned provisions of the convention are binding, in particular on persons having rights of custody who seek the assistance of a court of a Member State with the return of a child on the basis of the combined application of the two instruments in question.

89. In light of the foregoing, it appears to me that the area of the cross-border abduction of children is already governed, at least ‘to a large extent’, by the relevant common rules of EU law. Even though the provisions of the Brussels IIa Regulation, and of Article 11 thereof in particular, contemplate the continued application of the 1980 Hague Convention as between the Member States, that application must henceforth take effect by means of an obligation arising under EU law and through the medium of the regulation, that is to say, in conjunction with the particular rules laid down by the regulation, which take precedence over the corresponding provisions of the convention. ( 126 )

90. The content and the scope of the latter are different, inasmuch as the Brussels IIa Regulation established a system for the division of competences and cooperation between the Member State authorities which is both reinforced and improved by comparison with the mechanisms established by the convention, which have revealed some weaknesses, despite the real contribution they make. ( 127 ) To that end, the EU legislature employed four principal means. ( 128 ) First, the cases in which the immediate return of a child might be refused were defined restrictively. ( 129 ) Secondly, even in the event of a refusal to return a child pursuant to Article 13 of the convention, the courts of the Member State of origin of the child have the last word in ruling on the substantive merits of the rights of custody, with a view to dissuading abductors, if possible, or, in any event, not allowing them the benefit of a legal advantage. ( 130 ) Thirdly, the duration of the procedures was reduced. Fourthly, exequatur was abolished in respect of judgments on rights of access and judgments on the return of a child following abduction that are enforceable and have been duly certified by the courts of the Member States that have given them. In addition, the hearing of the child took on a degree of importance that it had not had under the 1980 Hague Convention. ( 131 )

91. I consider that one of the conditions inherent in the third situation contemplated by Article 3(2) TFEU, as defined in the case-law of the Court, is thus fulfilled to that extent. It remains for me to consider the last of those conditions, which concerns the repercussions which the international agreements referred to in the request for an opinion of the Court are likely to have on the common rules which in fact exist in the area in question.

3. The risk that the common rules in question might be affected by the international agreements at issue

92. As has already been pointed out, ( 132 ) the mere existence of common rules which already govern to a large extent the area to which the international agreements at issue apply is not in itself sufficient to establish exclusive external competence on the European Union’s part. It is also necessary for the agreements to have an adverse effect consisting in a risk that they will affect those rules or alter their scope, within the meaning of Article 3(2) TFEU, even if they do not give rise to any material contradiction. Such a risk may nevertheless arise from the mere fact that the international agreements contain provisions which are closely connected with the common rules in question. Indeed, it is possible that such a connection will make it more difficult to ensure the correct application and effectiveness of the provisions of EU law.

93. In the present case, there are a number of instances where such a connection between the two instruments in question could create a risk of an adverse effect. That is particularly true of the potential interplay between Article 11 of the Brussels IIa Regulation and Articles 12 and 13 of the 1980 Hague Convention, since the rules laid down in Article 11(2) to (8) either replace the corresponding provisions of the convention or circumscribe their application. ( 133 ) As the Commission has pointed out and illustrated with specific examples, ( 134 ) the difficulties are not merely hypothetical and could arise in practice in a number of ways.

94. In my view, the fact that the individual acceptance by Member States of the accession of third States could lead to variations in the way in which the international abduction of children is dealt with is not in itself immediately problematic. Indeed, such variations are already inherent in the system established by the 1980 Hague Convention, since the convention provides that the effects of the accession of a new contracting State vis-à-vis a State that is already party to the convention are subject to acceptance by the latter State, which makes it clear that the application of the provisions of the convention takes effect on the basis of bilateral relations. Moreover, from the point of view of EU law, a difference in regimes arises from the fact that the Kingdom of Denmark has not signed up to the system established by the Brussels IIa Regulation, ( 135 ) which means that it is the convention, and not the regulation, that applies in relations between the Kingdom of Denmark and the other Member States in the event of cross-border abduction, just as if it were a third State.

95. Nevertheless, I consider that if only some Member States accepted the accession of a third State to the 1980 Hague Convention, that could lead to complications in the interplay between the two instruments in relations between the Member States.

96. In particular, the simplified mechanism for the recognition and enforcement of return decisions given in another State which is provided for by the Brussels IIa Regulation, and in particular the abolition of exequatur in the case of certified return decisions, rests on the ‘cornerstone for the creation of a genuine judicial area’, which is the principle of mutual trust in the legal systems of the Member States, in particular as regards the equivalence of the legal protection which they afford, that being a principle peculiar to the European Union. ( 136 ) On the other hand, relations between the courts of the requested State and those of the State of origin are often inverted where the situation calls for interaction with a third State, particularly under the system established by the 1980 Hague Convention for assessing whether or not the overriding interest of the child lies in returning to the country where he or she had been residing. ( 137 )

97. Above all, the role played by the central authorities, in accordance with Articles 6 and 7 of the 1980 Hague Convention, ( 138 ) is one of the key elements of the system of cooperation established by the convention. It is therefore essential, as was rightly emphasised in the Commission’s abovementioned proposals for Council decisions, ( 139 ) that the acceptance by a Member State of the accession of a third State must be made subject to the pre-condition that the future contracting party has designated a central authority with responsibility, inter alia, for assisting European citizens in the event of the wrongful removal of children to that third State.

98. In my opinion, the mechanisms for dealing with the abduction of children established by the Brussels IIa Regulation in conjunction with the 1980 Hague Convention would be jeopardised if every Member State were free to determine the conditions under which it accepted the accession of third States to that convention. It appears to me to be essential that the reliability of any acceding third State, in so far as concerns judicial and administrative cooperation, should be assessed jointly under the coordination of the Council ( 140 ) pursuant to a proposal from the Commission. In the absence of such an initiative for concerted action, there is a risk of compromising the uniform and consistent application of the provisions of the Brussels IIa Regulation and the proper functioning of the system which it establishes, which would undermine the full effectiveness of the rules of EU law, according to the criteria for assessment defined by the Court of Justice. ( 141 )

99. I would add that, in accordance with the duty of sincere cooperation which they owe the European Union under the terms of Article 4(3) TEU, the Member States must refrain from concluding any agreement with a third State that could have such deleterious effects on the common rules. Indeed, the purpose of the conferral of exclusive external competence on the European Union in every area in which it has adopted rules in the exercise of its internal competence is, in particular, to ensure that the Member States do not undermine or undo action taken by the EU by means of action taken outside the EU. ( 142 ) This sincere cooperation is all the more necessary where, as in the present case, the power to conclude an international agreement in the area in question lies solely with the Member States. ( 143 )

100. As regards the foreseeable future development of EU law, as referred to in Opinion 1/03, ( 144 ) it cannot be ruled out that the Brussels IIa Regulation will be amended to extend its scope to external situations, as occurred with Regulation No 44/2001, the so-called ‘Brussels I Regulation’, whose provisions were recast ( 145 ) to that effect. ( 146 ) Indeed, it might seem opportune that the more stringent provisions for protection against cross-border abduction adopted within the European Union do not lead to discrimination against children habitually resident outside the EU. ( 147 ) However, there would need to be a sufficient degree of confidence in the legal systems of the third States concerned and the matter would require consultation. ( 148 )

101. In my opinion, the system for dealing with the cross-border abduction of children established by the Brussels IIa Regulation could be affected to a greater extent by the expansion of the scope of the cooperation mechanism under the 1980 Hague Convention to include new third States. Indeed, the convention has, in a certain fashion, been incorporated into the regulation, ( 149 ) with the result that the question of which third States acceding to the convention should be accepted is not without implications for the development of EU law. ( 150 )

102. Finally, it must be observed that, even though the 1980 Hague Convention may be regarded as operating on the basis of a series of bilateral relations between contracting States, any amendment of the wording of the convention would require the unanimous consent of all those States. Therefore, any new accession to the convention would increase the number of parties with which the Member States of the European Union would need to negotiate and reach a consensus in the event that the EU should wish to alter the content of the convention. Since the acceptance of the accession of a third State creates a new political situation and alters the parameters of the interplay between the Brussels IIa Regulation and the convention, it is, to my mind, essential that there be joint scrutiny within the European Union of the matter of accepting third States which accede to the convention, in particular with reference to the ability of those States to fulfil the obligations laid down by the convention and their political will to cooperate genuinely with the European Union.

103. Since the objective of the 1980 Hague Convention thus falls within an area already covered to a large extent by common rules, the effectiveness of which might be jeopardised by international agreements such as those at issue, that exercise by the European Union of its internal competence has the corollary of conferring on it exclusive external competence in the area. It follows that the Member States must accept the accession of third States to the convention in the interests of the European Union and in a coordinated manner.

104. That, in my view, is the necessary conclusion notwithstanding the real problems which could arise, in terms of the interests of abducted children, from any delay in international cooperation that could result from difficulties in rapidly achieving such concerted acceptance, since the delimitation of the sphere of the Europoean Union’s exclusive competence can only be effected in accordance with objective criteria. ( 151 )

105. Therefore, I recommend that, within the bounds of the admissibility of the request for an opinion, the Court answer the question posed by the Commission in the affirmative, that is to say, that it hold that the European Union has exclusive external competence.

VI – Conclusion

106. For the foregoing reasons, I propose that the Court: — declare the request for an opinion of the Court submitted by the Commission admissible in so far as it concerns the declarations by the Member States other than the Kingdom of Denmark of acceptance of the accession to the Hague Convention of 25 October 1980 on the Civil Aspects of International Child Abduction of the third States referred to in that request which had not yet been deposited when the request was submitted, and — answer the question posed by holding that the acceptance of the accession of third States to the Hague Convention falls within the exclusive external competence of the European Union.

( 1 ) Original language: French.

( 2 ) This is the first View to be delivered after the revision of the Rules of Procedure of the Court of Justice pursuant to which a single Advocate General is to be heard during the procedure, rather than all Advocates General (see recital 5 to and Article 196 et seq. of the Rules of Procedure).

( 3 ) The text of the convention and publications relating to it (including the Explanatory Report of E. Pérez-Vera) are available at the following address: http://www.hcch.net/index_en.php?act=conventions.text&cid= 24.

( 4 ) The Italian Government alone argues that the EU has exclusive competence, while the 20 or so other governments that have made submissions, in some cases, alternative submissions, on the substance of the question argue the opposite.

( 5 ) OJ 2003 L 338, p. 1.

( 6 ) On 1 March 2007, 4 May 2007, 27 May 2008, 9 March 2010, 6 December 2010, 28 December 2010, 6 April 2011 and 28 July 2011 respectively.

( 7 ) Those paragraphs provide that ‘[a]ny other State may accede to the Convention’, that ‘[t]he instrument of accession shall be deposited with the Ministry of Foreign Affairs of the Kingdom of the Netherlands’, and that ‘[t]he Convention shall enter into force for a State acceding to it on the first day of the third calendar month after the deposit of its instrument of accession’.

( 8 ) The fourth and fifth paragraphs provide that ‘[t]he accession will have effect only as regards the relations between the acceding State and such Contracting States as will have declared their acceptance of the accession. Such a declaration will also have to be made by any Member State ratifying, accepting or approving the Convention after an accession. Such declaration shall be deposited at the Ministry of Foreign Affairs of the Kingdom of the Netherlands; this Ministry shall forward, through diplomatic channels, a certified copy to each of the Contracting States’ and that ‘[t]he Convention will enter into force as between the acceding State and the State that has declared its acceptance of the accession on the first day of the third calendar month after the deposit of the declaration of acceptance’.

( 9 ) The eight proposals for Council decisions, which were annexed to the request for an opinion, concerned, in numeric order, the accession to the convention of Gabon (COM(2011) 904 final), Andorra (COM(2011) 908 final), the Seychelles (COM(2011) 909 final), the Russian Federation (COM(2011) 911 final), Albania (COM(2011) 912 final), Singapore (COM(2011) 915 final), Morocco (COM(2011) 916 final) and Armenia (COM(2011) 917 final). Each proposal provided that the Member States were to deposit simultaneously and by no later than two months after the adoption of the decision, a standard declaration of acceptance, in the interest of the European Union, of the accession of the third States concerned.

( 10 ) European Parliament resolution 2012/2791(RSP) of 22 November 2012 on the declaration of acceptance by the Member States, in the interest of the European Union, of the accession of eight third countries to the 1980 Hague Convention.

( 11 ) Lambreth, I., ‘Les aspects institutionnels de la dimension externe de la coopération judiciaire civile’, in La dimension externe de l’espace de liberté, de sécurité et de justice au lendemain de Lisbonne et de Stockholm: un bilan à mi-parcours, edited by M. Dony, Éditions de l’Université de Bruxelles, Brussels, 2012, p. 12 et seq., paragraph 17.

( 12 ) By way of example, the Republic of Latvia accepted the accession of the Republic of Albania on 3 July 2007. The current status of accessions to the 1980 Hague Convention and a detailed list of declarations of acceptance of those accessions may be found at the following addresses: http://www.hcch.net/index_en.php?act=conventions.status&cid= 24 and http://www.hcch.net/index_en.php?act=publications.details&pid= 3282&dtid336. It is clear from the information provided that other third States acceded to the convention after the Russian Federation and the same problem arises with regard to those States as is raised in the present request for an opinion.

( 13 ) Pursuant to Protocol No 22 on the position of Denmark, annexed to the EU and FEU Treaties, that Member State does not participate in the adoption of measures proposed on the basis of Title V of Part Three of the FEU Treaty, which relates to the area of freedom, security and justice, and in particular Chapter 3 of Title V on judicial cooperation in civil matters. Consequently, it is not bound by the Brussels IIA Regulation or subject to its application (recital 31 of the preamble to and Article 2(3) of that regulation).

( 14 ) Namely, the Czech, German, Estonian, Greek, French, Cypriot, Latvian, Lithuanian, Austrian, Polish and Romanian Governments. In addition, the Finnish Government has stated that, although it does not formally raise an objection of inadmissibility, the procedure for failure to fulfil obligations provided for by Article 258 TFEU would, in its view, be the most appropriate means of addressing the question raised in this case.

( 15 ) As may the Member States, the European Parliament and the Council.

( 16 ) The adjective ‘international’ is not expressly used in Article 218(11), but may be inferred from the fact that Article 218 appears in Title V of Part Five of the FEU Treaty, which is headed ‘International Agreements’.

( 17 ) Opinion 1/75 (EU:C:1975:145, especially p. 1360) and Opinion 1/78 (EU:C:1979:224, paragraph 30).

( 18 ) See, in particular, Opinion 2/91 (EU:C:1993:106, paragraph 3) and Opinion 1/08 (EU:C:2009:739, paragraphs 107 to 109).

( 19 ) I would clarify at this point that, contrary to what is implied in the Council’s observations on the admissibility of the request for an opinion, it is not the rejected proposals for Council decisions that are in issue in the present procedure, but rather the international agreements concluded by the Member States which those proposals purported to anticipate.

( 20 ) According to the European Parliament, an application for accession on the part of a third State and the acceptance of that accession on the part of the European Union, which triggers the application of the convention in dealings between the State in question and the European Union, together form an international commitment of a binding nature, which therefore constitutes an international agreement within the meaning of Article 218 TFEU.

( 21 ) The German Government asserts that a declaration of acceptance pursuant to Article 38 of the 1980 Hague Convention is not a component part of any accession agreement since the mere fact of depositing an instrument of accession and the passage of three months create rights and obligations under the convention for the new contracting State, and in particular the obligation to designate a central authority in accordance with Article 6 thereof.

( 22 ) The Court stated in Opinion 1/75 (EU:C:1975:145) that a request for an opinion may relate to ‘any undertaking entered into by entities subject to international law which has binding force, whatever its formal designation’ (my emphasis). See also Opinion 2/92 (EU:C:1995:83), paragraph 8.

( 23 ) The Vienna Convention was concluded on 23 May 1969 and entered into force on 27 January 1980 (United Nations Treaty Series, vol. 1155, p. 331). On ‘agreements in simplified form’ see Klabbers, J., The Concept of Treaty in International Law, Martinus Nijhoff, Leiden, 2006, pp. 46 and 73.

( 24 ) Article 11 provides that ‘[t]he consent of a State to be bound by a treaty may be expressed by signature, exchange of instruments constituting a treaty, ratification, acceptance, approval or accession, or by any other means if so agreed’.

( 25 ) In substance, that result is no different from that which would ensue if the Member States concluded with a third State a bilateral agreement the content of which is identical to that of the convention in accordance with the procedure laid down in Council Regulation (EC) No 664/2009 of 7 July 2009 establishing a procedure for the negotiation and conclusion of agreements between Member States and third countries concerning jurisdiction, recognition and enforcement of judgments and decisions in matrimonial matters, matters of parental responsibility and matters relating to maintenance obligations, and the law applicable to matters relating to maintenance obligations (OJ 2009 L 200, p. 46). On the delegation of competence following a Commission assessment, as provided for in that regulation, see Lambreth, I., op. cit. (footnote 11), paragraph 22 et seq.

( 26 ) This difference in drafting is all the more noticeable in that, before the Lisbon Treaty, Article 300(6) EC, which relates to the procedure for obtaining the Court’s opinion, was followed by a final paragraph 7 which implied that all the preceding paragraphs applied only to ‘agreements concluded under the conditions set out in this Article’, whereas that is no longer the case with the equivalent provision, Article 218(11) TFEU.

( 27 ) In Opinion 2/91 (EU:C:1993:106, paragraph 5), in support of its finding that the conditions for requesting an opinion of the Court had been satisfied, the Court observed that, ‘although ... the Community [could not] itself conclude [the convention in question], its external competence [could], if necessary, be exercised through the medium of the Member States acting jointly in the Community’s interest’ (my emphasis). On the possible indirect exercise of the European Union’s external competence, see also the judgment in Commission v Greece (C‑45/07, EU:C:2009:81), paragraph 31.

( 28 ) That restriction arises from the first paragraph of Article 37 and the first paragraph of Article 38 of the convention.

( 29 ) The European Community became a member of the HCCH on 3 April 2007 (see recital 3 of the preamble to Council Decision 2006/719/EC of 5 October 2006 on the accession of the Community to the Hague Conference on Private International Law (OJ 2006 L 297, p. 1)) and was succeeded, on 1 December 2009, by the European Union following the entry into force of the Lisbon Treaty. It was as a regional economic integration organisation that the Union acceded to the Hague Convention of 23 November 2007 on the International Recovery of Child Support and Other Forms of Family Maintenance, as is expressly provided for by Article 58(3) of that convention.

( 30 ) A similar restriction was addressed in Opinion 2/91 (EU:C:1993:106). Convention No 170 of the International Labour Organisation, in issue on that occasion, could be ratified only by the States that are members of that organisation and not by the Community. See, also, recitals 4 and 5 of the preamble to Council Decision 2014/52/EU of 28 January 2014 authorising Member States to ratify, in the interests of the European Union, the Convention concerning Safety in the Use of Chemicals at Work, 1990, of the International Labour Organization (Convention No 170) (OJ 2014 L 32, p. 33).

( 31 ) See footnote 9 to this View.

( 32 ) Article 81(3) TFEU provides that ‘measures concerning family law with cross-border implications shall be established by the Council, acting in accordance with a special legislative procedure. The Council shall act unanimously after consulting the European Parliament’.

( 33 ) See, to that effect, recitals F to H of European Parliament resolution 2012/2791, mentioned above.

( 34 ) Cremona, M., ‘Member States as Trustees of the Community Interest: Participating in International Agreements on the Behalf of the European Community’, European University of Florence Working Papers, Department of Law, 2009/17, p. 1 et seq.

( 35 ) See, for example, Council Decision 2014/52, mentioned above.

( 36 ) See, for example, the Monetary Agreement between the Government of the French Republic, on behalf of the European Community, and the Government of His Serene Highness the Prince of Monaco (OJ 2002 L 142, p. 59).

( 37 ) For example, the bilateral and regional agreements concluded under Regulation No 664/2009.

( 38 ) Rosas, A., ‘Exclusive, shared and national competence in the context of EU external relations: do such distinctions matter?’, in The European Union in the World, Essays in Honour of Marc Maresceau, edited by I. Govaere and others, Martinus Nijhoff, Leiden, 2014, pp. 32 and 33.

( 39 ) See point 31 of this View.

( 40 ) See, for example Council Decision 2003/93/EC of 19 December 2002 authorising the Member States, in the interest of the Community, to sign the 1996 Hague Convention on jurisdiction, applicable law, recognition, enforcement and cooperation in respect of parental responsibility and measures for the protection of children (OJ 2003 L 48, p. 1) and Council Decision 2008/431/EC of 5 June 2008 authorising certain Member States to ratify, or accede to, in the interest of the European Community, that same convention and authorising certain Member States to make a declaration on the application of the relevant internal rules of Community law (OJ 2008 L 151, p. 36).

( 41 ) See Rosas, A., ‘The status in EU Law of international agreements concluded by EU Member States’, Fordham International Law Journal, 2011, vol. 34, especially pp. 1331 to 1335 and 1344.

( 42 ) Ibidem, especially pp. 1333 and 1335.

( 43 ) Where the Union has exclusive competence but, as in the present case, lacks the capacity to be a contracting party to the agreement in question its role in the exercise of its exclusive competence is somewhat obscure from the point of view of third States (Rosas, A., ‘Exclusive, shared and national competence in the context of EU external relations: do such distinctions matter?’, op. cit. (footnote 38), p. 31, 33 and 42).

( 44 ) In Opinion 1/94 (EU:C:1994:384, paragraph 12), the Court stated that it could be called upon to give its opinion ‘at any time before the Community’s consent to be bound by the agreement is finally expressed. Unless and until that consent is given, the agreement remains an envisaged agreement’.

( 45 ) See point 31 of this View.

( 46 ) On this question generally, see Adam, S., La procédure d’avis devant la Cour de justice de l’Union européenne, in the series Droit de l’Union européenne — Thèses, Bruylant, Brussels, 2011, especially pp. 565 et seq.

( 47 ) That same requirement appears in Article 196(2) of the Rules of Procedure.

( 48 ) In order for a request for an opinion to be admissible, it is necessary — and also sufficient — that the decision-making process in relation to the draft agreement has reached a sufficiently advanced stage for the subject-matter of the agreement to be known, so that the Court can rule on the compatibility of that draft with the Treaties, even if a number of alternatives are still open and there remain differences of opinion on the drafting of the texts (Opinion 1/09, EU:C:2011:123, paragraph 53).

( 49 ) Opinion 1/75 (EU:C:1975:145, especially p. 1360). See also Opinion 1/09 (EU:C:2011:123), paragraph 47 and the case-law cited.

( 50 ) According to Opinion 2/94 (EU:C:1996:140, paragraph 6), a request for an opinion of the Court must be made ‘at a stage prior to conclusion of an agreement which is capable of giving rise to a dispute concerning the legality of a Community act which concludes, implements or applies it’.

( 51 ) Opinion 1/09 (EU:C:2011:123), paragraph 48 and the case-law cited.

( 52 ) See also Opinion 2/91 (EU:C:1993:106) and Decision 2014/52, mentioned above.

( 53 ) The Court pointed out in Opinion 3/94 (EU:C:1995:436, paragraphs 19 and 23) that ‘the preventive intent ... can no longer be achieved if the Court rules on an agreement which has already been concluded ... and there is accordingly no need to respond to [the] request [for an opinion]’.

( 54 ) See footnote 13 to this View.

( 55 ) For example, at that time, the Kingdom of Belgium and the Federal Republic of Germany had refrained from accepting the accession of the Gabonese Republic and the Russian Federation, the Republic of Bulgaria and the Republic of Croatia had accepted the accession of the Russian Federation but not of the other seven third States referred to in the request for an opinion, while the Portuguese Republic had not accepted the accession of any of the third States.

( 56 ) In its request (paragraph 8), the Commission submitted that ‘an opinion of the Court would in any event also put an end to the current practice of some Member States which have already accepted the accessions of third countries without a prior authorising decision of the Council, even though such a decision is required whenever an agreement falls within the exclusive competence of the Union’ (my emphasis). Although the Commission refers to a ‘current practice’, many of the acceptances were given in 2007, long before the request was made to the Court.

( 57 ) The Czech Republic has stated that, after the failure of its proposals for the adoption of a common position within the Council, the Commission first initiated against it and at least three other Member States the so-called EU Pilot procedure, which precedes the formal initiation of an action for failure to fulfil obligations. The Commission then changed its mind and submitted the present request for an opinion of the Court. The Republic of Poland has stated that the Commission has already brought an action for failure to fulfil obligations against certain Member States which have independently declared their acceptance of the accession of the Russian Federation to the 1980 Hague Convention.

( 58 ) That is to say, on the assumption that the Union’s exclusive external competence is established in this case.

( 59 ) Commission v United Kingdom (C‑466/98, EU:C:2002:624), Commission v Denmark (C‑467/98, EU:C:2002:625), Commission v Sweden (C‑468/98, EU:C:2002:626), Commission v Finland (C‑469/98, EU:C:2002:627), Commission v Belgium (C‑471/98, EU:C:2002:628), Commission v Luxembourg (C‑472/98, EU:C:2002:629), Commission v Austria (C‑475/98, EU:C:2002:630) and Commission v Germany (C‑476/98, EU:C:2002:631).

( 60 ) In particular, the principles relating to the burden of proof and the rights of the defence.

( 61 ) Indeed, in order for the Court to be able to give an opinion, it is necessary — and also sufficient — that at least one such agreement is still ‘envisaged’ within the meaning of Article 218(11) TFEU.

( 62 ) Such conflicts could arise between the content of the international agreements envisaged and the content of rules of EU law.

( 63 ) In particular, Article 216(1) TFEU provides that ‘[t]he Union may conclude an agreement with one or more third countries or international organisations where the Treaties so provide or where the conclusion of an agreement is necessary in order to achieve, within the framework of the Union’s policies, one of the objectives referred to in the Treaties, or is provided for in a legally binding Union act or is likely to affect common rules or alter their scope’.

( 64 ) See Opinion 2/91 (EU:C:1993:106), paragraph 4.

( 65 ) Recital 2 of the preamble to Council Decision 2006/719, mentioned above, and Annex II to that decision, entitled ‘Declaration of competence of the European Community specifying the matters in respect of which competence has been transferred to it by its Member States’, and in particular points 2 and 5. Nevertheless, the decision does not expressly specify the areas of work of the HCCH in relation to which the Community enjoys exclusive external competence (Rosas, A., ‘Exclusive, shared and national competence in the context of EU external relations: do such distinctions matter?’, op. cit. (footnote 38), p. 30).

( 66 ) With the exception of the Greek, French and Polish Governments, which suggest that the European Union might have no competence to accept the accession of third States to the 1980 Hague Convention.

( 67 ) See, inter alia, Commission v Council (‘the ERTA judgment’) (22/70, EU:C:1971:32), paragraphs 16 and 17, Opinion 2/94 (EU:C:1996:140), paragraph 26, and Opinion 1/03 (EU:C:2006:81), paragraph 114 and the case-law cited.

( 68 ) In particular, the Union’s entitlement to conclude such agreements is recognised, indirectly, in Article 2 of Protocol No 22 on the Position of Denmark, annexed to the EU and FEU Treaties, which mentions ‘international agreement[s] concluded by the Union pursuant to [Title V of Part Three of the FEU Treaty]’.

( 69 ) Declaration 36 on Article 218 TFEU, which concerns the negotiation and conclusion by the Member States of international agreements relating to the area of freedom, security and justice, confirms that ‘Member States may negotiate and conclude agreements with third countries ... in the areas covered by [Chapter 3] of Title V of Part Three in so far as such agreements comply with Union law’. That rule, which applies in the case of shared competence, in no way affects the principles governing the demarcation of shared competence from the exclusive competence of the Union which flow from the FEU Treaty and from case-law.

( 70 ) Some of them have submitted that competence is shared only in the alternative to their principal submission that the request for an opinion of the Court is inadmissible or that the Union has no external competence at all in the field.

( 71 ) See points 32 and 33 of this View.

( 72 ) EU:C:1971:32.

( 73 ) The quotation which follows is taken from point 6 of Annex II to the decision.

( 74 ) See Commission v Council, the ‘ERTA judgment’ (EU:C:1971:32), paragraph 16.

( 75 ) Opinion 1/76 (EU:C:1977:63) and Opinion 2/91 (EU:C:1993:106), Commission v Council, the ‘ERTA judgment’ (EU:C:1971:32), and Commission v Denmark (EU:C:2002:625).

( 76 ) Commission v Council, the ‘ERTA judgment’ (EU:C:1971:32), paragraph 17, and Commission v Denmark (EU:C:2002:625), paragraph 77. My emphasis.

( 77 ) Advocate General Bot has also recently noted that ‘the principle of parallelism between external and internal competences enshrined in the ERTA judgment [was] thus [made] conditional on the prior exercise of the European Union’s competence by the adoption of common rules, including in areas in which there is no common policy, and on common rules being affected by State action’ (opinion in Green Network, C‑66/13, EU:C:2014:156, point 39).

( 78 ) Advocate General Bot has explained (ibidem, point 43 et seq.) that, in the first group of judgments, it appeared to be sufficient if the areas covered, respectively, by the internal common rules and the international undertakings at issue coincided or even partially coincided (Commission v Council, the ‘ERTA judgment’, EU:C:1971:32, paragraphs 30 and 31, and Opinion 2/91, EU:C:1993:106, paragraph 25), while, in the second group of judgments, the Court took a stricter approach, holding that the rule of parallelism between external and internal competences came into play in three specific situations (Opinion 1/94, EU:C:1994:384, paragraphs 77, 95 and 96, and the ‘open skies’ judgments mentioned above, in particular, Commission v Denmark, EU:C:2002:625, paragraph 77 et seq.).

( 79 ) EU:C:2006:81. Subsequent Opinions offer no further clarification of the point.

( 80 ) That is to say, that the Community ‘acquires an exclusive external competence’ where it has ‘included in its internal legislative acts provisions relating to the treatment of nationals of non-member countries’ or has ‘expressly conferred on its institutions powers to negotiate with non-member countries’ or has ‘achieved complete harmonisation in a given area’ (Commission v Denmark, EU:C:2002:625, paragraphs 83 and 84 and the case-law cited).

( 81 ) Opinion 1/03 (EU:C:2006:81), paragraph 121.

( 82 ) Commission v Council, the ‘ERTA judgment’ (EU:C:1971:32), paragraph 31.

( 83 ) Opinion 1/03 (EU:C:2006:81), paragraph 122 and the case-law cited.

( 84 ) Ibidem, paragraph 126.

( 85 ) Opinion 2/91 (EU:C:1993:106), paragraph 25, Commission v Denmark (EU:C:2002:625), paragraph 82, and Commission v Germany (C‑433/03, EU:C:2005:462), paragraph 45.

( 86 ) Opinion in Green Network (EU:C:2014:156), points 48 to 50.

( 87 ) Criterion referred to in Opinion 2/91 (EU:C:1993:106), paragraph 25. My emphasis.

( 88 ) Opinion 1/03 (EU:C:2006:81), paragraph 126. My emphasis.

( 89 ) Ibidem, paragraph 128. My emphasis.

( 90 ) Ibidem, paragraph 124. My emphasis. This principle of the conferral of competences was also mentioned in Opinion 1/08 (EU:C:2009:739, paragraph 110) and is referred to in Article 5(1) TEU.

( 91 ) Namely, customs union, the establishing of the competition rules necessary for the functioning of the internal market, monetary policy for the Member States whose currency is the euro, the conservation of marine biological resources under the common fisheries policy and the common commercial policy.

( 92 ) See also the Opinion of Advocate General Sharpston in Commission v Council (C‑114/12, EU:C:2014:224), point 90.

( 93 ) EU:C:1993:106, paragraph 25. This criterion was subsequently applied on numerous occasions by the Court (see, in particular, the case-law referred to in footnote 25 to the Opinion of Advocate General Bot in Green Network (EU:C:2014:156)).

( 94 ) EU:C:2006:81, paragraphs 126 to 128.

( 95 ) Opinion in Commission v Council (C‑137/12, EU:C:2013:441), points 110 to 117.

( 96 ) Opinion in Commission v Council (EU:C:2014:224), especially points 81 to 97.

( 97 ) See, in particular, the observations submitted in the present case by the Commission and the Estonian, Irish, Cypriot, Portuguese and United Kingdom Governments and by the European Parliament and the Council. See also the Opinion of Advocate General Kokott in Commission v Council (EU:C:2013:441), point 112, and Adam, S., ‘Le mécanisme préjudiciel, limite fonctionnelle à la compétence externe de l’Union — Note sur l’avis 1/09’, Cahiers de droit européen, 2011, No 1, p. 277 et seq., footnote 52.

( 98 ) A similar form of words, ‘where the conclusion of an [international] agreement ... is likely to affect common rules or alter their scope’ appears in Article 216(1) TFEU, but without any further guidance as to the meaning that is to be given to that expression. On the content of Article 216(1) TFEU and the fact that the differences in some language versions between its formulation and that of Article 3(2) TFEU is irrelevant, see the Opinion of Advocate General Sharpston in Commission v Council (EU:C:2014:224), point 88.

( 99 ) An omission which was also noted by Advocate General Kokott in her Opinion in Commission v Council (EU:C:2013:441, point 111).

( 100 ) Final report of Working Group V ‘Complementary Competencies’ of 4 November 2002, CONV 375/1/02, p. 7, at: (http://european-convention.eu.int/pdf/reg/en/02/cv00/cv00375-re01.en02.pdf), and the Final report of