the problem of IUU fishing, as well as the United Kingdom adopted such a view. A number of other states took the position that flag state responsibility for IUU fishing should take the form of a general responsibility to perform due diligence with respect to vessels and their activities, rather than an obligation to assist in prosecutions or another more substantive requirement. In its Advisory Opinion issued on 2 April 2015, the Tribunal adopted the "due diligence" approach. The Tribunal found that flag states are under only a general obligation to take the necessary measures to ensure that their nationals and vessels flying their flag are not engaged in IUU fishing activities. This obligation may be satisfied by adhering to generally accepted international norms of fishing vessel regulation and complying with international treaties that indicate best practices. At the same time, the Tribunal found that in coastal waters the coastal state bears primary responsibility for preventing IUU fishing and not the flag state. Political processes EU action plan The EU helped draw up FAO's international plan of action to prevent, deter and eliminate IUU fishing, endorsed by the FAO Council in June 2001. The EU then developed its own plan to implement the commitments agreed at international level, and the European Commission's action plan for the eradication of IUU fishing was published in May 2002. It is intended to be implemented at four levels: At the EU level, more responsibility will be requested with regard to member state nationals acting under a flag of convenience. Moreover, market measures concerning fisheries products caught in violation of the international agreements will be adopted. In addition, information actions addressed to the fishing industry, consumers, and the public will be launched to raise their awareness. In the framework of Regional Fisheries Management Organisations, control and inspection plans would be adopted as well as specific conservation and management measures. In addition IUU vessels would be identified and monitored and their catches would be quantified. At the international level, concepts like genuine link would be defined, and a number of rights and obligations of the port state would be established. Moreover, the exchange of information on IUU activities and the international co-operation would be strengthened. In partnership with developing countries, the necessary means would be provided to enable them to effectively control fishing activities undertaken in waters under their jurisdiction. European Commission sanctions against states operating